Seven Clues to the Origin of Life by A.G. Cairns-Smith (1985)

The topic of the origin of life on the Earth is a branch of mineralogy. (p.99)

How did life begin? To be more precise, how did the inorganic chemicals formed in the early years of planet earth, on the molten rocks or in the salty sea or in the methane atmosphere, transform into ‘life’ – complex organisms which extract food from the environment and replicate, and from which all life forms today are ultimately descended? What, when and how was that first momentous step taken?

Thousands of biologists have devoted their careers to trying to answer this question, with the result that there are lots of speculative theories.

Alexander Graham Cairns-Smith (1931-2016) was an organic chemist and molecular biologist at the University of Glasgow, and this 120-page book was his attempt to answer the Big Question.

In a nutshell he suggested that life derived from self-replicating clay crystals. To use Wikipedia’s summary:

Clay minerals form naturally from silicates in solution. Clay crystals, like other crystals, preserve their external formal arrangement as they grow, snap, and grow further.

Clay crystal masses of a particular external form may happen to affect their environment in ways that affect their chances of further replication. For example, a ‘stickier’ clay crystal is more likely to silt up a stream bed, creating an environment conducive to further sedimentation.

It is conceivable that such effects could extend to the creation of flat areas likely to be exposed to air, dry, and turn to wind-borne dust, which could fall randomly in other streams.

Thus – by simple, inorganic, physical processes – a selection environment might exist for the reproduction of clay crystals of the ‘stickier’ shape.

Cairns-Smith’s book is densely argued, each chapter like a lecture or seminar packed with suggestive evidence about what we know about current life forms, a summary of the principles underlying Darwin’s theory of evolution, and about how we can slowly move backwards along the tree of life, speculating about how it developed.

But, as you can see from the summary above, in the end, it is just another educated guess.

Detective story

The blurb on the back and the introduction both claim the book is written in the style of a detective story. Oh no it isn’t. It is written in the style of a biology book – more precisely, a biology book which is looking at the underlying principles of life, the kind of abstract engineering principles underlying life – and all of these take quite some explaining, drawing in examples from molecular biology where required.

Sometimes (as in chapter 4 where he explains in detail how DNA and RNA and amino acids and proteins interact within a living cell) it becomes quite a demanding biology book.

What the author and publisher presumably mean is that, in attempt to sweeten the pill of a whole load of stuff about DNA and ribosomes, Cairns-Smith starts every chapter with a quote from a Sherlock Holmes story and from time to time claims to be pursuing his goal with Holmesian deduction.

You see Holmes, far from going for the easy bits first, would positively seek out those features in a case that were seemingly incomprehensible – ‘singular’ features he would call them… I think that the origin of life is a Holmesian problem. (p.ix)

Towards the very end, he remembers this metaphor and talks about ‘tracking down the suspect’ and ‘making an arrest’ (i.e. of the first gene machine, the origin of life). But this light dusting of Holmesiana doesn’t do much to conceal the sometimes quite demanding science, and the relentlessly pedagogical tone of the book.

Broad outline

1. Panspermia

First off, Cairns-Smith dismisses some of the other theories about the origin of life. He makes short work of the theories of Fred Hoyle and Francis Crick that organic life might have arrived on earth from outer space, carried in dust clouds or on meteors etc (Crick’s version of this was named ‘Panspermia’) . I agree with Cairns-Smith that all variations on this hypothesis just relocate the problem somewhere else, but don’t solve it.

Cairns-Smith states the problem in three really fundamental facts:

  1. There is life on earth
  2. All known living things are at root the same (using the same carbon-based energy-gathering and DAN-replicating biochemistry)
  3. All known living things are very complicated

2. The theory of chemical evolution

In his day (the 1970s and 80s) the theory of ‘chemical evolution’ was widely thought to address the origin of life problem. This stated that lot of the basic amino acids and sugars which we find in organisms are relatively simple and so might well have been created by accident in the great sloshing oceans and lakes of pre-life earth, and that they then – somehow – came together to make more complex molecules which – somehow – learned how to replicate.

But it’s precisely on the vagueness of that ‘somehow’ that Cairns-Smith jumps. The leap from a random soup of semi-amino acids washing round in a lake and the immensely detailed and complex machinery of life demonstrated by even a tiny living organism – he selects the bacterium Escherichia coli – is just too vast a cliff face to have been climbed at random, by accident. It’s like saying if you left a bunch of wires and bits of metal sloshing around in a lake long enough they would eventually make a MacBook Air.

Cairns-Smith zeroes in on four keys aspects of life on earth which help to disprove the ‘chemical evolution’ theory.

  1. Life forms are complex systems. It is the whole machine which makes sense of its components.
  2. The systems are highly interlocked: catalysts are needed to make proteins, but proteins are needed to make catalysts; nucleic acids are needed to make proteins, yet proteins are needed to make nucleic acids;
  3. Life forms are very complex.
  4. The system is governed by rules and conventions: the exact choice of the amino acid alphabet and the set of assignments of amino acid letters to nucleic acid words are examples.

3. The Miller-Urey experiments

Cairns-Smith then critiques the theory derived from the Miller-Urey experiments.

In 1953 a graduate student, Stanley Miller, and his professor, Harold Urey, performed an experiment that demonstrated how organic molecules could have spontaneously formed from inorganic precursors, under conditions like those posited by the Oparin-Haldane Hypothesis. The now-famous ‘Miller–Urey experiment’ used a highly reduced mixture of gases – methane, ammonia and hydrogen – to form basic organic monomers, such as amino acids. (Wikipedia)

Cairns-Smith spends four pages comprehensively demolishing this approach by showing that:

  1. the ultraviolet light its exponents claim could have helped synthesise organic molecules is in fact known to break covalent bonds and so degrade more than construct complex molecules
  2. regardless of light, most organic molecules are in fact very fragile and degrade easily unless kept in optimum conditions (i.e. inside a living cell)
  3. even if some organic molecules were created, organic chemists know only too well that there are hundreds of thousands of ways in which carbon, hydrogen, nitrogen and oxygen can combine, and most of them result in sticky sludges and tars in which nothing could ‘live’

So that:

  1. Only some of the molecules of life can be made this way
  2. Most of the molecules that would be made this way are emphatically not the ‘molecules of life’
  3. The ‘molecules of life’ are usually better made under conditions far most favourable than those obtaining back in the primordial soup era

He then does some back-of-a-matchbox calculations to speculate about how long it would take a random collection of organic molecules to ‘happen’ to all tumble together and create a life form: longer than the life of the universe, is his conclusion. No, this random approach won’t work.

Preliminary principles

Instead, he suggests a couple of principles of his own:

  1. That some and maybe all of the chemicals we now associate with ‘life’ were not present in the first replicating organisms; they came later; their exquisitely delicate interactivity suggests that they are the result not the cause of evolution
  2. Therefore, all lines of investigation which seek to account for the presence of the molecules of life are putting the cart before the horse: it isn’t the molecules which are important – it is the mechanism of replication with errors

Cairns-Smith thinks we should put the molecules of life question completely to one side, and instead seek for entirely inorganic systems which would replicate, with errors, so that the errors would be culled and more efficient ways of replicating tend to thrive on the available source material, beginning to create that dynamism and ‘sense of purpose’ which is one of life’s characteristics.

We keep coming to this idea that at some earlier phase of evolution, before life as we know it, there were other kinds of evolving system, other organisms that, in effect, invented our system. (p.61)

This seems, intuitively, like a more satisfying approach. Random forces will never make a MacBook Air and, as he has shown in chapter 4, even an entity like Escherichia coli is so staggeringly complex and amazingly finely-tuned as to be inconceivable as the product of chance.

Trying to show that complex molecules like ribosomes or RNA or amino acids – which rely on each other to be made and maintained, which cannot exist deprived of the intricately complicated interplay within each living cell – came about by chance is approaching the problem the wrong way. All these complex organic molecules must be the result of evolution. Evolution itself must have started with something much, much simpler – with the ‘invention’ of the basic engine, motor, the fundamental principle – and this is replication with errors. In other words:

Evolution started with ‘low-tech’ organisms that did not have to be, and probably were not made from, ‘the molecules of life’. (p.65)

Crystals

And it is at this point that Cairns-Smith introduces his Big Idea – the central role of clay crystals – in a chapter titled, unsurprisingly, ‘Crystals’ (pp.75-79).

He now explains in some detail the surprisingly complicated and varied world of clay crystals. These naturally form in various solutions and, if splashed up onto surfaces like rocks or stones, crystallise out into lattices, but the crystallisation process also commonly involves errors and mutations.

His description of the different types of crystals and their properties is fascinating – who knew there were so many types, shapes, patterns and processes, starting with an introduction to the processes of saturation and super-saturation. The point is that crystals naturally occur and naturally mutate. He lists the ways they can vary or diverge from their ‘pure’ forms: twinning, stacking errors, cation substitutions, growth in preferred directions, break-up along preferred planes (p.97).

There follows a chapter about the prevalence of crystals in mud and clay and, therefore, their widespread presence in the conditions of the early planet earth.

And then, finally, he explains the big leap whereby replicating crystals may have attracted to themselves other molecules.

There follows a process of natural selection for clay crystals that trap certain forms of molecules to their surfaces that may enhance their replication potential. Complex proto-organic molecules can be catalysed by the surface properties of silicates.

Genetic takeover of the crystals

It is at this point that he introduces the idea of a ‘genetic takeover’.

When complex molecules perform a ‘genetic takeover’ from their clay ‘vehicle’, they become an independent locus of replication – an evolutionary moment that might be understood as the first exaptation.

(Exaptation = ‘the process by which features acquire functions for which they were not originally adapted or selected’)

Cairns-Smith had already described this process – the ‘genetic takeover’ of an initial, non-organic process by more complex, potentially organic molecules – in his earlier, longer and far more technical book, Genetic Takeover: And the Mineral Origins of Life, published in 1982.

This book – the Seven Clues – is a much shorter, non-technical and more accessible popularisation of the earlier tome. Hence the frivolous references to Sherlock Holmes.

Proliferating crystals form the scaffold for molecules which learn to replicate without them

The final chapter explains how these very common and proliferating entities (clay crystals) might have formed into structures and arrangements which attracted – for purely chemical reasons – various elementary organic molecules to themselves.

Certain repeating structures might attract molecules which then build up into more complex molecules, into molecules which are more efficient at converting the energy of the sun into further molecular combinations. And thus the principle of replication with variation, and competition for resources among the various types of replicating molecule, would have been established.

Thoughts

At this point the book ends, his case presented. It has been a fascinating journey because a) it is interesting to learn about all the different shapes and types of clay crystal b) he forces the reader to think about the fundamental engineering and logistical aspects of life forms, to consider the underlying principles which must inform all life forms, which is challenging and rewarding.

But, even in his own terms, Cairns-Smith’s notion of more and more complex potentially organic molecules being haphazardly replicated on a framework of proliferating clay crystals is still a long, long, long way from even the most primitive life forms known to us, with their vastly complex structure of cell membrane, nucleus and internal sea awash with DNA-controlled biochemical processes.


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A Brief History of Time: From the Big Bang to Black Holes by Stephen Hawking (1988)

The whole history of science has been the gradual realisation that events do not happen in an arbitrary manner, but that they reflect a certain underlying order. (p.122)

This book was a publishing phenomenon when it was published in 1988. Nobody thought a book of abstruse musings about obscure theories of cosmology would sell, but it became a worldwide bestseller, selling more than 10 million copies in 20 years. It was on the London Sunday Times bestseller list for more than five years and was translated into 35 languages by 2001. So successful that Hawking went on to write seven more science books on his own, and co-author a further five.

Accessible As soon as you start reading you realise why. From the start is it written in a clear accessible way and you are soon won over to the frank, sensible, engaging tone of the author. He tells us he is going to explain things in the simplest way possible, with an absolute minimum of maths or equations (in fact, the book famously includes only one equation E = mc²).

Candour He repeatedly tells us that he’s going to explain things in the simplest possible way, and the atmosphere is lightened when Hawking – by common consent one of the great brains of our time – confesses that he has difficulty with this or that aspect of his chosen subject. (‘It is impossible to imagine a four-dimensional space. I personally find it hard enough to visualise three-dimensional space!’) We are not alone in finding it difficult!

Historical easing Also, like most of the cosmology books I’ve read, it takes a deeply historical view of the subject. He doesn’t drop you into the present state of knowledge with its many accompanying debates i.e. at the deep end. Instead he takes you back to the Greeks and slowly, slowly introduces us to their early ideas, showing why they thought what they thought, and how the ideas were slowly disproved or superseded.

A feel for scientific change So, without the reader being consciously aware of the fact, Hawking accustoms us to the basis of scientific enquiry, the fundamental idea that knowledge changes, and from two causes: from new objective observations, often the result of new technologies (like the invention of the telescope which enabled Galileo to make his observations) but more often from new ideas and theories being worked out, published and debated.

Hawking’s own contributions There’s also the non-trivial fact that, from the mid-1960s onwards, Hawking himself has made a steadily growing contribution to some of the fields he’s describing. At these points in the story, it ceases to be an objective history and turns into a first-person account of the problems as he saw them, and how he overcame them to develop new theories. It is quite exciting to look over his shoulder as he explains how and why he came up with the new ideas that made him famous. There are also hints that he might have trodden on a few people’s toes in the process, for those who like their science gossipy.

Thus it is that Hawking starts nice and slow with the ancient Greeks, with Aristotle and Ptolemy and diagrams showing the sun and other planets orbiting round the earth. Then we are introduced to Copernicus, who first suggested the planets orbit round the sun, and so on. With baby steps he takes you through the 19th century idea of the heat death of the universe, on to the discovery of the structure of the atom at the turn of the century, and then gently introduces you to Einstein’s special theory of relativity of 1905. (The special theory of relativity doesn’t take account of gravity, the general theory of relativity of 1915, does, take account of gravity).

Chapter 1 Our Picture of the Universe (pp.1-13)

Aristotle thinks earth is stationary. Calculates size of the earth. Ptolemy. Copernicus. In 1609 Galileo starts observing Jupiter using the recently invented telescope. Kepler suggests the planets move in ellipses not perfect circles. 1687 Isaac newton publishes Philosophiæ Naturalis Principia Mathematica (Mathematical Principles of Natural Philosophy) ‘probably the most important single work ever published in the physical sciences’, among many other things postulating a law of universal gravity. One implication of Newton’s theory is that the universe is vastly bigger than previously conceived.

In 1823 Heinrich Olbers posited his paradox which is, if the universe is infinite, the night sky out to be as bright as daylight because the light from infinite suns would reach us. Either it is not infinite or it has some kind of limit, possibly in time i.e. a beginning. The possible beginning or end of the universe were discussed by Immanuel Kant in his obscure work A Critique of Pure Reason  (1781). Various other figures debated variations on this theme until in 1929 Edwin Hubble made the landmark observation that, wherever you look, distant galaxies are moving away from us i.e. the universe is expanding. Working backwards from this observation led physicists to speculate that the universe was once infinitely small and infinitely dense, in a state known as a singularity, which must have exploded in an event known as the big bang.

He explains what a scientific theory is:

A theory is just a model of the universe, or a restricted part of it, and a set of rules that relate quantities in the model to observations that we make… A theory is a good theory if it satisfies two requirements: it must accurately describe a large class of observations on the basis of a model that contains only a few arbitrary elements, and it must make definite predictions about the results of future observations.

A theory is always provisional. The more evidence proving it, the stronger it gets. But it only takes one good negative observation to disprove a theory.

Today scientists describe the universe in terms of two basic partial theories – the general theory of relativity and quantum mechanics. They are the great intellectual achievements of the first half of this century.

But they are inconsistent with each other. One of the major endeavours of modern physics is to try and unite them in a quantum theory of gravity.

Chapter 2 Space and Time (pp.15-34)

Aristotle thought everything in the universe was naturally at rest. Newton disproved this with his first law – whenever a body is not acted on by any force it will keep on moving in a straight line at the same speed. Newton’s second law stats that, When a body is acted on by a force it will accelerate or change its speed at a rate that is proportional to the force. Newton’s law of gravity states that every particle attracts every other particle in the universe with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centres. But like Aristotle, Newton believed all the events he described took place in a kind of big static arena named absolute space, and that time was an absolute constant. The speed of light was also realised to be a constant. In 1676 Danish astronomer Ole Christensen estimated the speed of light to be 140,000 miles per second. We now know it is 186,000 miles per second. In the 1860s James Clerk Maxwell unified the disparate theories which had been applied to magnetism and electricity.

In 1905 Einstein published his theory of relativity. It is derived not from observation but from Einstein working through in his head the consequences and shortcomings of the existing theories. Newton had posited a privileged observer, someone outside the universe who was watching it as if a play on a stage. From this privileged position a number of elements appeared constant, such as time.

Einstein imagines a universe in which there is no privileged outside point of view. We are all inside the universe and all moving. The theory threw up a number of consequences. One is that energy is equal to mass times the speed of light squared, or E = mc². Another is that nothing may travel faster than the speed of light. Another is that, as an object approaches the speed of light its mass increases. One of its most disruptive ideas is that time is relative. Different observes, travelling at different speeds, will see a beam of light travel take different times to travel a fixed distance. Since Einstein has made it axiomatic that the speed of light is fixed, and we know the distance travelled by the light is fixed, then time itself must appear different to different observers. Time is something that can change, like the other three dimensions. Thus time can be added to the existing three dimensions to create space-time.

The special theory of relativity was successful in explaining how the speed of light appears the same to all observers, and describing what happens to things when they move close to the speed of light. But it was inconsistent with Newton’s theory of gravity which says objects attract each other with a force related to the distance between them. If you move on of the objects the force exerted on the other object changes immediately. This cannot be if nothing can travel faster than the speed of light, as the special theory of relativity postulates. Einstein spent the ten or so years from 1905 onwards attempting to solve this difficulty. Finally, in 1915, he published the general theory of relativity.

The revolutionary basis of this theory is that space is not flat, a consistent  continuum or Newtonian stage within which events happen and forces interact in a sensible way. Space-time is curved or warped by the distribution of mass or energy within it, and gravity is a function of this curvature. Thus the earth is not orbiting around the sun in a circle, it is following a straight line in warped space.

The mass of the sun curves space-time in such a way that although the earth follows a straight line in four-dimensional pace-time, it appears to us to move along a circular orbit in three-dimensional space. (p.30)

In fact, at a planetary level Einstein’s maths is only slightly different from Newton’s but it predicts a slight difference in the orbit of Mercury which observations have gone on to prove. Also, the general theory predicts that light will bend, following a straight line but through space that is warped or curved by gravity. Thus the light from a distant star on the far side of the sun will bend as it passes close to the sun due to the curvature in space-time caused by the sun’s mass. And it was an expedition to West Africa in 1919 to observe an eclipse, which showed that light from distant stars did in fact bend slightly as it passed the sun, which helped confirm Einstein’s theory.

Newton’s laws of motion put an end to the idea of absolute position in space. The theory of relativity gets rid of absolute time.

Hence the thought experiment popularised by a thousand science fiction books that astronauts who set off in a space ship which gets anywhere near the speed of light will experience a time which is slower than the people they leave behind on earth.

In the theory of relativity there is no unique absolute time, but instead each individual has his own personal measure of time that depends on where he is and how he is moving. (p.33)

Obviously, since most of us are on planet earth, moving at more or less the same speed, everyone’s personal ‘times’ coincide. Anyway, the key central implication of Einstein’s general theory of relativity is this:

Before 1915, space and time were thought of as a fixed arena in which events took place, but which was not affected by what happened in it. This was true even of the special theory of relativity. Bodies moved, forces attracted and repelled, but time and space simply continued, unaffected. It was natural to think that space and time went on forever.

the situation, however, is quite different in the general theory of relativity. Space and time are now dynamic quantities. : when a body moves, or a force acts, it affects the curvature of space and time – and in turn the structure of space-time affects the way in which bodies move and forces act. Space and time not only affect but also are affected by everything that happens in the universe. (p.33)

This view of the universe as dynamic and interacting, by demolishing the old eternal static view, opened the door to a host of new ways of conceiving how the universe might have begun and might end.

Chapter 3 The Expanding Universe (pp.35-51)

Our modern picture of the universe dates to 1924 when American astronomer Edwin Hubble demonstrated that ours is not the only galaxy. We now know the universe is home to some hundred million galaxies, each containing some hundred thousand million stars. We live in a galaxy that is about one hundred thousand light-years across and is slowly rotating. Hubble set about cataloguing the movement of other galaxies and in 1929 published his results which showed that they are all moving away from us, and that, the further away a galaxy is, the faster it is moving.

The discovery that the universe is expanding was one of the great intellectual revolutions of the twentieth century. (p.39)

From Newton onwards there was a universal assumption that the universe was infinite and static. Even Einstein invented a force he called ‘the cosmological constant’ in order to counter the attractive power of gravity and preserve the model of a static universe. It was left to Russian physicist Alexander Friedmann to seriously calculate what the universe would look like if it was expanding.

In 1965 two technicians, Arno Penzias and Robert Wilson, working at Bell Telephone Laboratories discovered a continuous hum of background radiation coming from all parts of the sky. This echoed the theoretical work being done by two physicists, Bob Dicke and Jim Peebles, who were working on a suggestion made by George Gamow that the early universe would have been hot and dense. They posited that we should still be able to see the light from this earliest phase but that it would, because the redshifting, appear as radiation. Penzias and Wilson were awarded the Nobel Prize in 1987.

How can the universe be expanding? Imagine blowing up a balloon with dots (or little galaxies) drawn on it: they all move apart from each other and the further apart they are, the larger the distance becomes; but there is no centre to the balloon. Similarly the universe is expanding but not into anything. There is no outside. If you set out to travel to the edge you would find no edge but instead find yourself flying round the periphery and end up back where you began.

There are three possible states of a dynamic universe. Either 1. it will expand against the contracting force of gravity until the initial outward propulsive force is exhausted and gravity begins to win; it will stop expanding, and start to contract. Or 2. it is expanding so fast that the attractive, contracting force of gravity never wins, so the universe expands forever and matter never has time to clump together into stars and planets. Or 3. it is expanding at just the right speed to escape collapsing back in on itself, but but so fast as to make the creation of matter impossible. This is called the critical divide. Physicists now believe the universe is expanding at just around the value of the critical divide, though whether it is just under or just above (i.e. the universe will eventually cease expanding, or not) is not known.

Dark matter We can calculate the mass of all the stars and galaxies in the universe and it is a mystery that our total is only about a hundredth of the mass that must exist to explain the gravitational behaviour of stars and galaxies. In other words, there must a lot of ‘dark matter’ which we cannot currently detect in order for the universe to be shaped the way it is.

So we don’t know what the likely future of the universe is (endless expansion or eventual contraction) but all the Friedmann models do predict that the universe began in an infinitely dense, infinitely compact, infinitely hot state – the singularity.

Because mathematics cannot really handle infinite numbers, this means that the general theory of relativity… predicts that there is a point in the universe where the theory itself breaks down… In fact, all our theories of science are formulated on the assumption that space-time is smooth and nearly flat, so they break down at the big bang singularity, where the curvature of space-time is infinite. (p.46)

Opposition to the theory came from Hermann Bondi, Thomas Gold and Fred Hoyle who formulated the steady state theory of the universe i.e. it has always been and always will be. All that is needed to explain the slow expansion is the appearance of new particles to keep it filled up, but the rate is very low (about one new particle per cubic kilometre per year). They published it in 1948 and worked through all its implications for the next few decades, but it was killed off as a theory by the 1965 observations of the cosmic background radiation.

He then explains the process whereby he elected to do a PhD expanding Roger Penrose’s work on how a dying star would collapse under its own weight to a very small size. The collaboration resulted in a joint 1970 paper which proved that there must have been a big bang, provided only that the theory of general relativity is correct, and the universe contains as much matter as we observe.

If the universe really did start out as something unimaginably small then, from the 1970s onwards, physicists turned their investigations to what happens to matter at microscopic levels.

Chapter 4 The Uncertainty Principle (pp.53-61)

1900 German scientist Max Planck suggests that light, x-rays and other waves can only be emitted at an arbitrary wave, in packets he called quanta. He theorised that the higher the frequency of the wave, the more energy would be required. This would tend to restrict the emission of high frequency waves. In 1926 Werner Heisenberg expanded on these insights to produce his Uncertainty Principle. In order to locate a particle in order to measure its position and velocity you need to shine a light on it. One has to use at least one quantum of energy. However, exposing the particle to this quantum will disturb the velocity of the particle.

In other words, the more accurately you try to measure the position of the particle, the less accurately you can measure its speed, and vice versa. (p.55)

Heisenberg showed that the uncertainty in the position of the particle times the uncertainty in its velocity times the mass of the particle can never be smaller than a certain quantity, which is known as Planck’s constant. For the rest of the 1920s Heisenberg, Erwin Schrödinger and Paul Dirac reformulated mechanics into a new theory titled quantum mechanics. In this theory particles no longer have separate well-defined positions and velocities, instead they have a general quantum state which is a combination of position and velocity.

Quantum mechanics introduces an unavoidable element of unpredictability or randomness into science. (p.56)

Also, particles can no longer be relied on to be particles. As a result of Planck and Heisenberg’s insights, particles have to be thought of as sometimes behaving like waves, sometimes like particles. In 1913 Niels Bohr had suggested that electrons circle round a nucleus at certain fixed points, and that it takes energy to dislodge them from these optimum orbits. Quantum theory helped explain Bohr’s theory by conceptualising the circling electrons not as particles but as waves. If electrons are waves, as they circle the nucleus, their wave lengths would cancel each other out unless they are perfect numbers. The frequency of the waves have to be able to circle the nucleus in perfect integers. This defines the height of the orbits electrons can take.

Chapter 5 Elementary Particles and Forces of Nature (pp.63-79)

A chapter devoted to the story of how we’ve come to understand the world of sub-atomic particles. Starting (as usual) with Aristotle and then fast-forwarding through Galton, Einstein’s paper on Brownian motion, J.J. Thomson’s discovery of electrons, and, in 1911, Ernest Rutherford’s demonstration that atoms are made up of tiny positively charged nucleus around which a number of tiny positively charged particles, electrons, orbit. Rutherford thought the nuclei contained ‘protons’, which have a positive charge and balance out the negative charge of the electrons. In 1932 James Chadwick discovered the nucleus contains neutrons, same mass as the proton but no charge.

In 1965 quarks were discovered by Murray Gell-Mann. In fact scientists went on to discover six types, up, down, strange, charmed, bottom and top quarks. A proton or neutron is made up of three quarks.

He explains the quality of spin. Some particles have to be spin twice to return to their original appearance. They have spin 1/2. All the matter we can see in the universe has the spin 1/2. Particles of spin 0, 1, and 2 give rise to the forces between the particles.

Pauli’s exclusionary principle: two similar particles cannot exist in the same state, they cannot have the same position and the same velocity. The exclusionary principle is vital since it explains why the universe isn’t a big soup of primeval particles. The particles must be distinct and separate.

In 1928 Paul Dirac explained why the electron must rotate twice to return to its original position. He also predicted the existence of the positron to balance the electron. In 1932 the positron was discovered and Dirac was awarded a Nobel Prize.

Force carrying particles can be divided into four categories according to the strength of the force they carry and the particles with which they interact.

  1. Gravitational force, the weakest of the four forces by a long way.
  2. The electromagnetic force interacts with electrically charged particles like electrons and quarks.
  3. The weak nuclear force, responsible for radioactivity. In findings published in 1967 Abdus Salam and Steven Weinberg suggested that in addition to the photon there are three other spin-1 particles known collectively as massive vector bosons. Initially disbelieved, experiments proved them right and they collected the Nobel Prize in 1979. In 1983 the team at CERN proved the existence of the three particles, and the leaders of this team also won the Nobel Prize.
  4. The strong nuclear force holds quarks together in the proton and neutron, and holds the protons and neutrons together in the nucleus. This force is believed to be carried by another spin-1 particle, the gluon. They have a property named ‘confinement’ which is that you can’t have a quark of a single colour, the number of quarks bound together must cancel each other out.

The idea behind the search for a Grand Unified Theory is that, at high enough temperature, all the particles would behave in the same way, i.e. the laws governing the four forces would merge into one law.

Most of the matter on earth is made up of protons and neutrons, which are in turn made of quarks. Why is there this preponderance of quarks and not an equal number of anti-quarks?

Hawking introduces us to the notion that all the laws of physics obey three separate symmetries known as C, P and T. In 1956 two American physicists suggested that the weak force does not obey symmetry C. Hawking then goes on to explain more about the obedience or lack of obedience to the rules of symmetry of particles at very high temperatures, to explain why quarks and matter would outbalance anti-quarks and anti-matter at the big bang in a way which, frankly, I didn’t understand.

Chapter 6 Black Holes (pp.81-97)

In a sense, all the preceding has been just preparation, just a primer to help us understand the topic which Hawking spent the 1970s studying and which made his name – black holes.

The term black hole was coined by John Wheeler in 1969. Hawking explains the development of ideas about what happens when a star dies. When a star is burning, the radiation of energy in the forms of heat and light counteracts the gravity of its mass. When it runs out of fuel, gravity takes over and the star collapses in on itself. The young Indian physicist Subrahmanyan Chandrasekhar calculated that a cold star with a mass of more than one and a half times the mass of our sin would not be able to support itself against its own gravity and contract to become a ‘white dwarf’ with a radius of a few thousand miles and a density of hundreds of tones per square inch.

The Russian Lev Davidovich Landau speculated that the same sized star might end up in a different state. Chandrasekhar had used Pauli’s exclusionary principle as applied to electrons i.e. calculated the smallest densest state the mass could reach assuming no electron can be in the place of any other electron. Landau calculated on the basis of the exclusionary principle repulsion operative between neutrons and protons. Hence his model is known as the ‘neutron star’, which would have a radius of only ten miles or so and a density of hundreds of millions of tonnes per cubic inch.

(In an interesting aside Hawking tells us that physics was railroaded by the vast Manhattan Project to build an atomic bomb, and then to build a hydrogen bomb, throughout the 1940s and 50s. This tended to sideline large-scale physics about the universe. It was only the development of a) modern telescopes and b) computer power, that revived interest in astronomy.)

A black hole is what you get when the gravity of a collapsing star becomes so high that it prevents light from escaping its gravitational field. Hawking and Penrose showed that at the centre of a black hole must be a singularity of infinite density and space-time curvature.

In 1967 the study of black holes was revolutionised by Werner Israel. He showed that, according to general relativity, all non-rotating black holes must be very simple and perfectly symmetrical.

Hawking then explains several variations on this theory put forward by Roger Penrose, Roy Kerr, Brandon Carter who proved that a hole would have an axis of symmetry. Hawking himself confirmed this idea. In 1973 David Robinson proved that a black hole had to have ‘a Kerr solution’. In other words, no matter how they start out, all black holes end up looking the same, a belief summed up in the pithy phrase, ‘A black hole has no hair’.

What is striking about all this is that it was pure speculation, derived entirely from mathematical models without a shred of evidence from astronomy.

Black holes are one of only a fairly small number of cases in the history of science in which a theory was developed in great detail as a mathematical model before there was any evidence from observations that it was correct. (p.92)

Hawking then goes on to list the best evidence we have for black holes, which is surprisingly thin. Since they are by nature invisible black holes can only be deduced by their supposed affect on nearby stars or systems. Given that black holes were at the centre of Hawking’s career, and are the focus of these two chapters, it is striking that there is, even now, very little direct empirical evidence for their existence.

(Eerily, as I finished reading A Brief History of Time, the announcement was made on 10 April 2019 that the first ever image has been generated of a black hole –

Theory predicts that other stars which stray close to a black hole would have clouds of gas attracted towards it. As this matter falls into the black hole it will a) be stripped down to basic sub-atomic particles b) make the hole spin. Spinning would make the hole acquire a magnetic field. The magnetic field would shoot jets of particles out into space along the axis of rotation of the hole. These jets should be visible to our telescopes.

First ever image of a black hole, captured the Event Horizon Telescope (EHT). The hole is 40 billion km across, and 500 million trillion km away

Chapter 7 Black Holes Ain’t So Black (pp.99-113)

Black holes are not really black after all. They glow like a hot body, and the smaller they are, the hotter they glow. Again, Hawking shares with us the evolution of his thinking on this subject, for example how he was motivated in writing a 1971 paper about black holes and entropy at least partly in irritation against another researcher who he felt had misinterpreted his earlier results.

Anyway, it all resulted in his 1973 paper which showed that a black hole ought to emit particles and radiation as if it were a hot body with a temperature that depends only on the black hole’s mass.

The reasoning goes thus: quantum mechanics tells us that all of space is fizzing with particles and anti-particles popping into existence, cancelling each other out, and disappearing. At the border of the event horizon, particles and anti-particles will be popping into existence as everywhere else. But a proportion of the anti-particles in each pair will be sucked inside the event horizon, so that they cannot annihilate their partners, leaving the positive particles to ping off into space. Thus, black holes should emit a steady stream of radiation!

If black holes really are absorbing negative particles as described above, then their negative energy will result in negative mass, as per Einstein’s most famous equation, E = mc² which shows that the lower the energy, the lower the mass. In other words, if Hawking is correct about black holes emitting radiation, then black holes must be shrinking.

Gamma ray evidence suggests that there might be 300 black holes in every cubic light year of the universe. Hawking then goes on to estimate the odds of detecting a black hole a) in steady existence b) reaching its final state and blowing up. Alternatively we could look for flashes of light across the sky, since on entering the earth’s atmosphere gamma rays break up into pairs of electrons and positrons. No clear sightings have been made so far.

(Threaded throughout the chapter has been the notion that black holes might come in two types: one which resulted from the collapse of stars, as described above. And others which have been around since the start of the universe as a function of the irregularities of the big bang.)

Summary: Hawking ends this chapter by claiming that his ‘discovery’ that radiation can be emitted from black holes was ‘the first example of a prediction that depended in an essential way on both the great theories of this century, general relativity and quantum mechanics’. I.e. it is not only an interesting ‘discovery’ in its own right, but a pioneering example of synthesising the two theories.

Chapter 8 The Origin and Fate of the Universe (pp.115-141)

This is the longest chapter in the book and I found it the hardest to follow. I think this is because it is where he makes the big pitch for His Theory, for what’s come to be known as the Hartle-Hawking state. Let Wikipedia explain:

Hartle and Hawking suggest that if we could travel backwards in time towards the beginning of the Universe, we would note that quite near what might otherwise have been the beginning, time gives way to space such that at first there is only space and no time. Beginnings are entities that have to do with time; because time did not exist before the Big Bang, the concept of a beginning of the Universe is meaningless. According to the Hartle-Hawking proposal, the Universe has no origin as we would understand it: the Universe was a singularity in both space and time, pre-Big Bang. Thus, the Hartle–Hawking state Universe has no beginning, but it is not the steady state Universe of Hoyle; it simply has no initial boundaries in time or space. (Hartle-Hawking state Wikipedia article)

To get to this point Hawking begins by recapping the traditional view of the ‘hot big bang’, i.e. the almost instantaneous emergence of matter from a state of infinite mass, energy and density and temperature.

This is the view first put forward by Gamow and Alpher in 1948, which predicted there would still be very low-level background radiation left over from the bang – which was then proved with the discovery of the cosmic background radiation in 1965.

Hawking gives a picture of the complete cycle of the creation of the universe through the first generation of stars which go supernova blowing out into space the heavier particles which then go into second generation stars or clouds of gas and solidify into things like planet earth.

In a casual aside, he gives his version of the origin of life on earth:

The earth was initially very hot and without an atmosphere. In the course of time it cooled and acquired an atmosphere from the emission of gases from the rocks. This early atmosphere was not one in which we could have survived. It contained no oxygen, but a lot of other gases that are poisonous to us, such as hydrogen sulfide. There are, however, other primitive forms of life that can flourish under such conditions. It is thought that they developed in the oceans, possibly as a result of chance combinations of atoms into large structures, called macromolecules, which were capable of assembling other atoms in the ocean into similar structures. They would thus have reproduced themselves and multiplied. In some cases there would have been errors in the reproduction. Mostly these errors would have been such that the new macromolecule could not reproduce itself and eventually would have been destroyed. However, a few of the errors would have produced new macromolecules that were even better at reproducing themselves. They would have therefore had an advantage and would have tended to replace the original macromolecules. In this way a process of evolution was started that led to the development of more and more complicated, self-reproducing organisms. The first primitive forms of life consumed various materials, including hydrogen sulfide, and released oxygen. This gradually changed the atmosphere to the composition that it has today and allowed the development of higher forms of life such as fish, reptiles, mammals, and ultimately the human race. (p.121)

(It’s ironic that he discusses the issue so matter-of-factly, demonstrating that, for him at least, the matter is fairly cut and dried and not worth lingering over. Because, of course, for scientists who’ve devoted their lives to the origins-of-life question it is far from over. It’s a good example of the way that every specialist thinks that their specialism is the most important subject in the world, the subject that will finally answer the Great Questions of Life whereas a) most people have never heard about the issues b) wouldn’t understand them and c) don’t care.)

Hawking goes on to describe chaotic boundary conditions and describe the strong and the weak anthropic principles. He then explains the theory proposed by Alan Guth of inflation i.e. the universe, in the first milliseconds after the big bang, underwent a process of enormous hyper-growth, before calming down again to normal exponential expansion. Hawking describes it rather differently from Barrow and Davies. He emphasises that, to start with, in a state of hypertemperature and immense density, the four forces we know about and the spacetime dimensions were all fused into one. They would be in ‘symmetry’. Only as the early universe cooled would it have undergone a ‘phase transition’ and the symmetry between forces been broken.

If the temperature fell below the phase transition temperature without symmetry being broken then the universe would have a surplus of energy and it is this which would have cause the super-propulsion of the inflationary stage. The inflation theory:

  • would allow for light to pass from one end of the (tiny) universe to the other and explains why all regions of the universe appear to have the same properties
  • explain why the rate of expansion of the universe is close to the critical rate required to make it expand for billions of years (and us to evolve)
  • would explain why there is so much matter in the universe

Hawking then gets involved in the narrative explaining how he and others pointed out flaws in Guth’s inflationary model, namely that the phase transition at the end of the inflation ended in ‘bubble’s which expanded to join up. But Hawking and others pointed out that the bubbles were expanding so fat they could never join up. In 1981 the Russian Andre Linde proposed that the bubble problem would be solved if  a) the symmetry broke slowly and b) the bubbles were so big that our region of the universe is all contained within a single bubble. Hawking disagreed, saying Linde’s bubbles would each have to be bigger than the universe for the maths to work out, and counter-proposing that the symmetry broke everywhere at the same time, resulting in the uniform universe we see today. Nonetheless Linde’s model became known as the ‘new inflationary model’, although Hawking considers it invalid.

[In these pages we get a strong whiff of cordite. Hawking is describing controversies and debates he has been closely involved in and therefore takes a strongly partisan view, bending over backwards to be fair to colleagues, but nonetheless sticking to his guns. In this chapter you get a strong feeling for what controversy and debate within this community must feel like.)

Hawking prefers the ‘chaotic inflationary model’ put forward by Linde in 1983, in which there is no phase transition or supercooling, but which relies on quantum fluctuations.

At this point he introduces four ideas which are each challenging and which, taken together, mark the most difficult and confusing part of the book.

First he says that, since Einstein’s laws of relativity break down at the moment of the singularity, we can only hope to understand the earliest moments of the universe in terms of quantum mechanics.

Second, he says he’s going to use a particular formulation of quantum mechanics, namely Richard Feynman’s idea of ‘a sum over histories’. I think this means that Feynman said that in quantum mechanics we can never know precisely which route a particle takes, the best we can do is work out all the possible routes and assign them probabilities, which can then be handled mathematically.

Third, he immediately points out that working with Feynman’s sum over histories approach requires the use of ‘imaginary’ time, which he then goes on to explain.

To avoid the technical difficulties with Feynman’s sum over histories, one must use imaginary time. (p.134)

And then he points out that, in order to use imaginary time, we must use Euclidean space-time instead of ‘real’ space-time.

All this happens on page 134 and was too much for me to understand. On page 135 he then adds in Einstein’s idea that the gravitational field us represented by curved space-time.

It is now that he pulls all these ideas together to assert that, whereas in the classical theory of gravity, which is based on real space-time there are only two ways the universe can behave – either it has existed infinitely or it had a beginning in a singularity at a finite point in time; in the quantum theory of gravity, which uses Euclidean space-time, in which the time direction is on the same footing as directions in space it is possible:

for space-time to be finite in extent and yet to have no singularities that formed a boundary or edge.

In Hawking’s theory the universe would be finite in duration but not have a boundary in time because time would merge with the other three dimensions, all of which cease to exist during and just after a singularity. Working backwards in time, the universe shrinks but it doesn’t shrink, as a cone does, to a single distinct point – instead it has a smooth round bottom with no distinct beginning.

The Hartle-Hawking no boundary Hartle and Hawking No-Boundary Proposal

The Hartle-Hawking no boundary Hartle and Hawking No-Boundary Proposal

Finally Hawking points out that this model of a no-boundary universe derived from a Feynman interpretation of quantum gravity does not give rise to all possible universes, but only to a specific family of universes.

One aspect of these histories of the universe in imaginary time is that none of them include singularities – which would seem to render redundant all the work Hawking had done on black holes in ‘real time’. He gets round this by saying that both models can be valid, but in order to demonstrate different things.

It is simply a matter of which is the more useful description. (p.139)

He winds up the discussion by stating that further calculations based on this model explain the two or three key facts about the universe which all theories must explain i.e. the fact that it is clumped into lumps of matter and not an even soup, the fact that it is expanding, and the fact that the background radiation is minutely uneven in some places suggesting very early irregularities. Tick, tick, tick – the no-boundary proposal is congruent with all of them.

It is a little mind-boggling, as you reach the end of this long and difficult chapter, to reflect that absolutely all of it is pure speculation without a shred of evidence to support it. It is just another elegant way of dealing with the problems thrown up by existing observations and by trying to integrate quantum mechanics with Einsteinian relativity. But whether it is ‘true’ or not, not only is unproveable but also is not really the point.

Chapter 9 The Arrow of Time (pp.143-153)

If Einstein’s theory of general relativity is correct and light always appears to have the same velocity to all observers, no matter what position they’re in or how fast they’re moving, THEN TIME MUST BE FLEXIBLE. Time is not a fixed constant. Every observer carries their own time with them.

Hawking points out that there are three arrows of time:

  • the thermodynamic arrow of time which obeys the Second Law of Thermodynamics namely that entropy, or disorder, increases – there are always many more disordered states than ordered ones
  • the psychological arrow of time which we all perceive
  • the cosmological arrow of time, namely the universe is expanding and not contracting

Briskly, he tells us that the psychological arrow of time is based on the thermodynamic one: entropy increases and our lives experience that and our minds record it. For example, human beings consume food – which is a highly ordered form of energy – and convert it into heat – which is a highly disordered form.

Hawking tells us that he originally thought that, if the universe reach a furthest extent and started to contract, disorder (entropy) would decrease, and everything in the universe would happen backwards. Until Don Page and Raymond Laflamme, in their different ways, proved otherwise.

Now he believes that the contraction would not occur until the universe had been almost completely thinned out and all the stars had died i.e. the universe had become an even soup of basic particles. THEN it would start to contract. And so his current thinking is that there would be little or no thermodynamic arrow of time (all thermodynamic processes having come to an end) and all of this would be happening in a universe in which human beings could not exist. We will never live to see the contraction phase of the universe. If there is a contraction phase.

Chapter 10: The Unification of Physics (pp.155-169)

The general theory of relativity and quantum mechanics both work well for their respective scales (stars and galaxies, sub-atomic particles) but cannot be made to mesh, despite fifty of more years of valiant attempts. Many of the attempts produce infinity in their results, so many infinities that a strategy has been developed called ‘renormalisation’ which gets rid of the infinities, although Hawking conceded is ‘rather dubious mathematically’.

Grand Unified Theories is the term applied to attempts to devise a theory (i.e. a set of mathematical formulae) which will take account of the four big forces we know about: electromagnetism, gravity, the strong nuclear force and the weak nuclear force.

In the mid-1970s some scientists came up with the idea of ‘supergravity’ which postulated a ‘superparticle’, and the other sub-atomic particles variations on the super-particle but with different spins. According to Hawking the calculations necessary to assess this theory would take so long nobody has ever done it.

So he moves onto string theory i.e. the universe isn’t made up of particles but of open or closed ‘strings’, which can join together in different ways to form different particles. However, the problem with string theory is that, because of the mathematical way they are expressed, they require more than four dimensions. A lot more. Hawking mentions anywhere from ten up to 26 dimensions. Where are all these dimensions? Well, strong theory advocates say they exist but are very very small, effectively wrapped up into sub-atomic balls, so that you or I never notice them.

Rather simplistically, Hawking lists the possibilities about a complete unified theory. Either:

  1. there really is a grand unified theory which we will someday discover
  2. there is no ultimate theory but only an infinite sequence of possibilities which will describe the universe with greater and greater, but finite accuracy
  3. there is no theory of the universe at all, and events will always seems to us to occur in a random way

This leads him to repeat the highfalutin’ rhetoric which all physicists drop into at these moments, about the destiny of mankind etc. Discovery of One Grand Unified Theory:

would bring to an end a long and glorious chapter in the history of humanity’s intellectual struggle to understand the universe. But it would also revolutionise the ordinary person’s understanding of the laws that govern the universe. (p.167)

I profoundly disagree with this view. I think it is boilerplate, which is a phrase defined as ‘used in the media to refer to hackneyed or unoriginal writing’.

Because this is not just the kind of phrasing physicists use when referring to the search for GUTs, it’s the same language biologists use when referring to the quest to understand how life derived from inorganic chemicals, it’s the same language the defenders of the large Hadron Collider use to justify spending billions of euros on the search for ever-smaller particles, it’s the language used by the guys who want funding for the Search for Extra-Terrestrial Intelligence), it’s the kind of language used by the scientists bidding for funding for the Human Genome Project.

Each of these, their defenders claim, is the ultimate most important science project, quest and odyssey ever,  and when they find the solution it will for once and all answer the Great Questions which have been tormenting mankind for millennia. Etc. Which is very like all the world’s religions claiming that their God is the only God. So a) there is a pretty obvious clash between all these scientific specialities which each claim to be on the brink of revealing the Great Secret.

But b) what reading this book and John Barrow’s Book of Universes convinces me is that i) we are very far indeed from coming even close to a unified theory of the universe and more importantly ii) if one is ever discovered, it won’t matter.

Imagine for a moment that a new iteration of string theory does manage to harmonise the equations of general relativity and quantum mechanics. How many people in the world are really going to be able to understand that? How many people now, currently, have a really complete grasp of Einsteinian relativity and Heisenbergian quantum uncertainty in their strictest, most mathematical forms? 10,000? 1000,000 earthlings?

If and when the final announcement is made who would notice, who would care, and why would they care? If the final conjunction is made by adapting string theory to 24 dimensions and renormalising all the infinities in order to achieve a multi-dimensional vision of space-time which incorporates both the curvature of gravity and the unpredictable behaviour of sub-atomic particles – would this really

revolutionise the ordinary person’s understanding of the laws that govern the universe?

Chapter 11 Conclusion (pp.171-175)

Recaps the book and asserts that his and James Hartle’s no-boundary model for the origin of the universe is the first to combine classic relativity with Heisenberg uncertainty. Ends with another rhetorical flourish of trumpets which I profoundly disagree with for the reasons given above.

If we do discover a complete theory, it should in time be understandable in broad principle by everyone, not just a few scientists. Then we shall all, philosophers, scientists, and just ordinary people, be able to take part in the discussion of the question of why it is that we and the universe exist. If we find the answer to that, it would be the ultimate triumph of human reason. (p.175)

Maybe I’m wrong, but I think this is a hopelessly naive view of human nature and culture. Einstein’s general theory has been around for 104 years, quantum mechanics for 90 years. Even highly educated people understand neither of them, and what Hawking calls ‘just ordinary people’ certainly don’t – and it doesn’t matter. 

Thoughts

Of course the subject matter is difficult to understand, but Hawking makes a very good fist of putting all the ideas into simple words and phrases, avoiding all formulae and equations, and the diagrams help a lot.

My understanding is that A Brief History of Time was the first popular science to put all these ideas before the public in a reasonably accessible way, and so opened the floodgates for countless other science writers, although hardly any of the ideas in it felt new to me since I happen to have just reread the physics books by Barrow and Davies which cover much the same ground and are more up to date.

But my biggest overall impression is how provisional so much of it seems. You struggle through the two challenging chapters about black holes – Hawking’s speciality – and then are casually told that all this debating and arguing over different theories and model-making had gone on before any black holes were ever observed by astronomers. In fact, even when Hawking died, in 2018, no black holes had been conclusively identified. It’s a big shame he didn’t live to see this famous photograph being published and confirmation of at least the existence of the entity he devoted so much time to theorising about.


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The Book of Universes by John D. Barrow (2011)

This book is twice as long and half as good as Barrow’s earlier primer, The Origin of the Universe.

In that short book Barrow focused on the key ideas of modern cosmology – introducing them to us in ascending order of complexity, and as simply as possible. He managed to make mind-boggling ideas and demanding physics very accessible.

This book – although it presumably has the merit of being more up to date (published in 2011 as against 1994) – is an expansion of the earlier one, an attempt to be much more comprehensive, but which, in the process, tends to make the whole subject more confusing.

The basic premise of both books is that, since Einstein’s theory of relativity was developed in the 1910s, cosmologists and astronomers and astrophysicists have:

  1. shown that the mathematical formulae in which Einstein’s theories are described need not be restricted to the universe as it has traditionally been conceived; in fact they can apply just as effectively to a wide variety of theoretical universes – and the professionals have, for the past hundred years, developed a bewildering array of possible universes to test Einstein’s insights to the limit
  2. made a series of discoveries about our actual universe, the most important of which is that a) it is expanding b) it probably originated in a big bang about 14 billion years ago, and c) in the first few milliseconds after the bang it probably underwent a period of super-accelerated expansion known as the ‘inflation’ which may, or may not, have introduced all kinds of irregularities into ‘our’ universe, and may even have created a multitude of other universes, of which ours is just one

If you combine a hundred years of theorising with a hundred years of observations, you come up with thousands of theories and models.

In The Origin of the Universe Barrow stuck to the core story, explaining just as much of each theory as is necessary to help the reader – if not understand – then at least grasp their significance. I can write the paragraphs above because of the clarity with which The Origin of the Universe explained it.

In The Book of Universes, on the other hand, Barrow’s aim is much more comprehensive and digressive. He is setting out to list and describe every single model and theory of the universe which has been created in the past century.

He introduces the description of each model with a thumbnail sketch of its inventor. This ought to help, but it doesn’t because the inventors generally turn out to be polymaths who also made major contributions to all kinds of other areas of science. Being told a list of Paul Dirac’s other major contributions to 20th century science is not a good way for preparing your mind to then try and understand his one intervention on universe-modelling (which turned, in any case, out to be impractical and lead nowhere).

Another drawback of the ‘comprehensive’ approach is that a lot of these models have been rejected or barely saw the light of day before being disproved or – more complicatedly – were initially disproved but contained aspects or insights which turned out to be useful forty years later, and were subsequently recycled into revised models. It gets a bit challenging to try and hold all this in your mind.

In The Origin of the Universe Barrow sticks to what you could call the canonical line of models, each of which represented the central line of speculation, even if some ended up being disproved (like Hoyle and Gold and Bondi’s model of the steady state universe). Given that all of this material is pretty mind-bending, and some of it can only be described in advanced mathematical formulae, less is definitely more. I found The Book of Universes simply had too many universes, explained too quickly, and lost amid a lot of biographical bumpf summarising people’s careers or who knew who or contributed to who’s theory. Too much information.

One last drawback of the comprehensive approach is that quite important points – which are given space to breathe and sink in in The Origin of the Universe are lost in the flood of facts in The Book of Universes.

I’m particularly thinking of Einstein’s notion of the cosmological constant which was not strictly necessary to his formulations of relativity, but which Einstein invented and put into them solely in order to counteract the force of gravity and ensure his equations reflected the commonly held view that the universe was in a permanent steady state.

This was a mistake and Einstein is often quoted as admitting it was the biggest mistake of his career. In 1965 scientists discovered the cosmic background radiation which proved that the universe began in an inconceivably intense explosion, that the universe was therefore expanding and that the explosive, outward-propelling force of this bang was enough to counteract the contracting force of the gravity of all the matter in the universe without any need for a hypothetical cosmological constant.

I understand this (if I do) because in The Origin of the Universe it is given prominence and carefully explained. By contrast, in The Book of Universes it was almost lost in the flood of information and it was only because I’d read the earlier book that I grasped its importance.

The Book of Universes

Barrow gives a brisk recap of cosmology from the Sumerians and Egyptians, through the ancient Greeks’ establishment of the system named after Ptolemy in which the earth is the centre of the solar system, on through the revisions of Copernicus and Galileo which placed the sun firmly at the centre of the solar system, on to the three laws of Isaac Newton which showed how the forces which govern the solar system (and more distant bodies) operate.

There is then a passage on the models of the universe generated by the growing understanding of heat and energy acquired by Victorian physicists, which led to one of the most powerful models of the universe, the ‘heat death’ model popularised by Lord Kelvin in the 1850s, in which, in the far future, the universe evolves to a state of complete homegeneity, where no region is hotter than any other and therefore there is no thermodynamic activity, no life, just a low buzzing noise everywhere.

But this is all happens in the first 50 pages and is just preliminary throat-clearing before Barrow gets to the weird and wonderful worlds envisioned by modern cosmology i.e. from Einstein onwards.

In some of these models the universe expands indefinitely, in others it will reach a peak expansion before contracting back towards a Big Crunch. Some models envision a static universe, in others it rotates like a top, while other models are totally chaotic without any rules or order.

Some universes are smooth and regular, others characterised by clumps and lumps. Some are shaken by cosmic tides, some oscillate. Some allow time travel into the past, while others threaten to allow an infinite number of things to happen in a finite period. Some end with another big bang, some don’t end at all. And in only a few of them do the conditions arise for intelligent life to evolve.

The Book of Universes then goes on, in 12 chapters, to discuss – by my count – getting on for a hundred types or models of hypothetical universes, as conceived and worked out by mathematicians, physicists, astrophysicists and cosmologists from Einstein’s time right up to the date of publication, 2011.

A list of names

Barrow namechecks and briefly explains the models of the universe developed by the following (I am undertaking this exercise partly to remind myself of everyone mentioned, partly to indicate to you the overwhelming number of names and ideas the reader is bombarded with):

  • Aristotle
  • Ptolemy
  • Copernicus
  • Giovanni Riccioli
  • Tycho Brahe
  • Isaac Newton
  • Thomas Wright (1771-86)
  • Immanuel Kant (1724-1804)
  • Pierre Laplace (1749-1827) devised what became the standard Victorian model of the universe
  • Alfred Russel Wallace (1823-1913) discussed the physical conditions of a universe necessary for life to evolve in it
  • Lord Kelvin (1824-1907) material falls into the central region of the universe and coalesce with other stars to maintain power output over immense periods
  • Rudolf Clausius (1822-88) coined the word ‘entropy’ in 1865 to describe the inevitable progress from ordered to disordered states
  • William Jevons (1835-82) believed the second law of thermodynamics implies that universe must have had a beginning
  • Pierre Duhem (1961-1916) Catholic physicist accepted the notion of entropy but denied that it implied the universe ever had a beginning
  • Samuel Tolver Preson (1844-1917) English engineer and physicist, suggested the universe is so vast that different ‘patches’ might experience different rates of entropy
  • Ludwig Boltzmann and Ernst Zermelo suggested the universe is infinite and is already in a state of thermal equilibrium, but just with random fluctuations away from uniformity, and our galaxy is one of those fluctuations
  • Albert Einstein (1879-1955) his discoveries were based on insights, not maths: thus he saw the problem with Newtonian physics is that it privileges an objective outside observer of all the events in the universe; one of Einstein’s insights was to abolish the idea of a privileged point of view and emphasise that everyone is involved in the universe’s dynamic interactions; thus gravity does not pass through a clear, fixed thing called space; gravity bends space.

The American physicist John Wheeler once encapsulated Einstein’s theory in two sentences:

Matter tells space how to curve. Space tells matter how to move. (quoted on page 52)

  • Marcel Grossmann provided the mathematical underpinning for Einstein’s insights
  • Willem de Sitter (1872-1934) inventor of, among other things, the de Sitter effect which represents the effect of the curvature of spacetime, as predicted by general relativity, on a vector carried along with an orbiting body – de Sitter’s universe gets bigger and bigger for ever but never had a zero point; but then de Sitter’s model contains no matter
  • Vesto Slipher (1875-1969) astronomer who discovered the red shifting of distant galaxies in 1912, the first ever empirical evidence for the expansion of the galaxy
  • Alexander Friedmann (1888-1925) Russian mathematician who produced purely mathematical solutions to Einstein’s equation, devising models where the universe started out of nothing and expanded a) fast enough to escape the gravity exerted by its own contents and so will expand forever or b) will eventually succumb to the gravity of its own contents, stop expanding and contract back towards a big crunch. He also speculated that this process (expansion and contraction) could happen an infinite number of times, creating a cyclic series of bangs, expansions and contractions, then another bang etc
A graphic of the oscillating or cyclic universe (from Discovery magazine)

A graphic of the oscillating or cyclic universe (from Discovery magazine)

  • Arthur Eddington (1882-1944) most distinguished astrophysicist of the 1920s
  • George Lemaître (1894-1966) first to combine an expanding universe interpretation of Einstein’s equations with the latest data about redshifting, and show that the universe of Einstein’s equations would be very sensitive to small changes – his model is close to Eddington’s so that it is often called the Eddington-Lemaître universe: it is expanding, curved and finite but doesn’t have a beginning
  • Edwin Hubble (1889-1953) provided solid evidence of the redshifting (moving away) of distant galaxies, a main plank in the whole theory of a big bang, inventor of Hubble’s Law:
    • Objects observed in deep space – extragalactic space, 10 megaparsecs (Mpc) or more – are found to have a redshift, interpreted as a relative velocity away from Earth
    • This Doppler shift-measured velocity of various galaxies receding from the Earth is approximately proportional to their distance from the Earth for galaxies up to a few hundred megaparsecs away
  • Richard Tolman (1881-1948) took Friedmann’s idea of an oscillating universe and showed that the increased entropy of each universe would accumulate, meaning that each successive ‘bounce’ would get bigger; he also investigated what ‘lumpy’ universes would look like where matter is not evenly spaced but clumped: some parts of the universe might reach a maximum and start contracting while others wouldn’t; some parts might have had a big bang origin, others might not have
  • Arthur Milne (1896-1950) showed that the tension between the outward exploding force posited by Einstein’s cosmological constant and the gravitational contraction could actually be described using just Newtonian mathematics: ‘Milne’s universe is the simplest possible universe with the assumption that the universe s uniform in space and isotropic’, a ‘rational’ and consistent geometry of space – Milne labelled the assumption of Einsteinian physics that the universe is the same in all places the Cosmological Principle
  • Edmund Fournier d’Albe (1868-1933) posited that the universe has a hierarchical structure from atoms to the solar system and beyond
  • Carl Charlier (1862-1934) introduced a mathematical description of a never-ending hierarchy of clusters
  • Karl Schwarzschild (1873-1916) suggested  that the geometry of the universe is not flat as Euclid had taught, but might be curved as in the non-Euclidean geometries developed by mathematicians Riemann, Gauss, Bolyai and Lobachevski in the early 19th century
  • Franz Selety (1893-1933) devised a model for an infinitely large hierarchical universe which contained an infinite mass of clustered stars filling the whole of space, yet with a zero average density and no special centre
  • Edward Kasner (1878-1955) a mathematician interested solely in finding mathematical solutions to Einstein’s equations, Kasner came up with a new idea, that the universe might expand at different rates in different directions, in some parts it might shrink, changing shape to look like a vast pancake
  • Paul Dirac (1902-84) developed a Large Number Hypothesis that the really large numbers which are taken as constants in Einstein’s and other astrophysics equations are linked at a deep undiscovered level, among other things abandoning the idea that gravity is a constant: soon disproved
  • Pascual Jordan (1902-80) suggested a slight variation of Einstein’s theory which accounted for a varying constant of gravitation as through it were a new source of energy and gravitation
  • Robert Dicke (1916-97) developed an alternative theory of gravitation
  • Nathan Rosen (1909-995) young assistant to Einstein in America with whom he authored a paper in 1936 describing a universe which expands but has the symmetry of a cylinder, a theory which predicted the universe would be washed over by gravitational waves
  • Ernst Straus (1922-83) another young assistant to Einstein with whom he developed a new model, an expanding universe like those of Friedman and Lemaître but which had spherical holes removed like the bubbles in an Aero, each hole with a mass at its centre equal to the matter which had been excavated to create the hole
  • Eugene Lifschitz (1915-85) in 1946 showed that very small differences in the uniformity of matter in the early universe would tend to increase, an explanation of how the clumpy universe we live in evolved from an almost but not quite uniform distribution of matter – as we have come to understand that something like this did happen, Lifshitz’s calculations have come to be seen as a landmark
  • Kurt Gödel (1906-1978) posited a rotating universe which didn’t expand and, in theory, permitted time travel!
  • Hermann Bondi, Thomas Gold and Fred Hoyle collaborated on the steady state theory of a universe which is growing but remains essentially the same, fed by the creation of new matter out of nothing
  • George Gamow (1904-68)
  • Ralph Alpher and Robert Herman in 1948 showed that the ratio of the matter density of the universe to the cube of the temperature of any heat radiation present from its hot beginning is constant if the expansion is uniform and isotropic – they calculated the current radiation temperature should be 5 degrees Kelvin – ‘one of the most momentous predictions ever made in science’
  • Abraham Taub (1911-99) made a study of all the universes that are the same everywhere in space but can expand at different rates in different directions
  • Charles Misner (b.1932) suggested ‘chaotic cosmology’ i.e. that no matter how chaotic the starting conditions, Einstein’s equations prove that any universe will inevitably become homogenous and isotropic – disproved by the smoothness of the background radiation. Misner then suggested the Mixmaster universe, the  most complicated interpretation of the Einstein equations in which the universe expands at different rates in different directions and the gravitational waves generated by one direction interferes with all the others, with infinite complexity
  • Hannes Alfvén devised a matter-antimatter cosmology
  • Alan Guth (b.1947) in 1981 proposed a theory of ‘inflation’, that milliseconds after the big bang the universe underwent a swift process of hyper-expansion: inflation answers at a stroke a number of technical problems prompted by conventional big bang theory; but had the unforeseen implication that, though our region is smooth, parts of the universe beyond our light horizon might have grown from other areas of inflated singularity and have completely different qualities
  • Andrei Linde (b.1948) extrapolated that the inflationary regions might create sub-regions in  which further inflation might take place, so that a potentially infinite series of new universes spawn new universes in an ‘endlessly bifurcating multiverse’. We happen to be living in one of these bubbles which has lasted long enough for the heavy elements and therefore life to develop; who knows what’s happening in the other bubbles?
  • Ted Harrison (1919-2007) British cosmologist speculated that super-intelligent life forms might be able to develop and control baby universe, guiding the process of inflation so as to promote the constants require for just the right speed of growth to allow stars, planets and life forms to evolve. Maybe they’ve done it already. Maybe we are the result of their experiments.
  • Nick Bostrom (b.1973) Swedish philosopher: if universes can be created and developed like this then they will proliferate until the odds are that we are living in a ‘created’ universe and, maybe, are ourselves simulations in a kind of multiverse computer simulation

Although the arrival of Einstein and his theory of relativity marks a decisive break with the tradition of Newtonian physics, and comes at page 47 of this 300-page book, it seemed to me the really decisive break comes on page 198 with the publication Alan Guth’s theory of inflation.

Up till the Guth breakthrough, astrophysicists and astronomers appear to have focused their energy on the universe we inhabit. There were theoretical digressions into fantasies about other worlds and alternative universes but they appear to have been personal foibles and everyone agreed they were diversions from the main story.

However, the idea of inflation, while it solved half a dozen problems caused by the idea of a big bang, seems to have spawned a literally fantastic series of theories and speculations.

Throughout the twentieth century, cosmologists grew used to studying the different types of universe that emerged from Einstein’s equations, but they expected that some special principle, or starting state, would pick out one that best described the actual universe. Now, unexpectedly, we find that there might be room for many, perhaps all, of these possible universes somewhere in the multiverse. (p.254)

This is a really massive shift and it is marked by a shift in the tone and approach of Barrow’s book. Up till this point it had jogged along at a brisk rate namechecking a steady stream of mathematicians, physicists and explaining how their successive models of the universe followed on from or varied from each other.

Now this procedure comes to a grinding halt while Barrow enters a realm of speculation. He discusses the notion that the universe we live in might be a fake, evolved from a long sequence of fakes, created and moulded by super-intelligences for their own purposes.

Each of us might be mannequins acting out experiments, observed by these super-intelligences. In which case what value would human life have? What would be the definition of free will?

Maybe the discrepancies we observe in some of the laws of the universe have been planted there as clues by higher intelligences? Or maybe, over vast periods of time, and countless iterations of new universes, the laws they first created for this universe where living intelligences could evolve have slipped, revealing the fact that the whole thing is a facade.

These super-intelligences would, of course, have computers and technology far in advance of ours etc. I felt like I had wandered into a prose version of The Matrix and, indeed, Barrow apologises for straying into areas normally associated with science fiction (p.241).

Imagine living in a universe where nothing is original. Everything is a fake. No ideas are ever new. There is no novelty, no originality. Nothing is ever done for the first time and nothing will ever be done for the last time… (p.244)

And so on. During this 15-page-long fantasy the handy sequence of physicists comes to an end as he introduces us to contemporary philosophers and ethicists who are paid to think about the problem of being a simulated being inside a simulated reality.

Take Robin Hanson (b.1959), a research associate at the Future of Humanity Institute of Oxford University who, apparently, advises us all that we ought to behave so as to prolong our existence in the simulation or, hopefully, ensure we get recreated in future iterations of the simulation.

Are these people mad? I felt like I’d been transported into an episode of The Outer Limits or was back with my schoolfriend Paul, lying in a summer field getting stoned and wondering whether dandelions were a form of alien life that were just biding their time till they could take over the world. Why not, man?

I suppose Barrow has to include this material, and explain the nature of the anthropic principle (p.250), and go on to a digression about the search for extra-terrestrial life (p.248), and discuss the ‘replication paradox’ (in an infinite universe there will be infinite copies of you and me in which we perform an infinite number of variations on our lives: what would happen if you came face to face with one of your ‘copies?? p.246) – because these are, in their way, theories – if very fantastical theories – about the nature of the universe and he his stated aim is to be completely comprehensive.

The anthropic principle Observations of the universe must be compatible with the conscious and intelligent life that observes it. The universe is the way it is, because it has to be the way it is in order for life forms like us to evolve enough to understand it.

Still, it was a relief when he returned from vague and diffuse philosophical speculation to the more solid territory of specific physical theories for the last forty or so pages of the book. But it was very noticeable that, as he came up to date, the theories were less and less attached to individuals: modern research is carried out by large groups. And he increasingly is describing the swirl of ideas in which cosmologists work, which often don’t have or need specific names attached. And this change is denoted, in the texture of the prose, by an increase in the passive voice, the voice in which science papers are written: ‘it was observed that…’, ‘it was expected that…’, and so on.

  • Edward Tryon (b.1940) American particle physicist speculated that the entire universe might be a virtual fluctuation from the quantum vacuum, governed by the Heisenberg Uncertainty Principle that limits our simultaneous knowledge of the position and momentum, or the time of occurrence and energy, of anything in Nature.
  • George Ellis (b.1939) created a catalogue of ‘topologies’ or shapes which the universe might have
  • Dmitri Sokolov and Victor Shvartsman in 1974 worked out what the practical results would be for astronomers if we lived in a strange shaped universe, for example a vast doughnut shape
  • Yakob Zeldovich and Andrei Starobinsky in 1984 further explored the likelihood of various types of ‘wraparound’ universes, predicting the fluctuations in the cosmic background radiation which might confirm such a shape
  • 1967 the Wheeler-De Witt equation – a first attempt to combine Einstein’s equations of general relativity with the Schrödinger equation that describes how the quantum wave function changes with space and time
  • the ‘no boundary’ proposal – in 1982 Stephen Hawking and James Hartle used ‘an elegant formulation of quantum  mechanics introduced by Richard Feynman to calculate the probability that the universe would be found to be in a particular state. What is interesting is that in this theory time is not important; time is a quality that emerges only when the universe is big enough for quantum effects to become negligible; the universe doesn’t technically have a beginning because the nearer you approach to it, time disappears, becoming part of four-dimensional space. This ‘no boundary’ state is the centrepiece of Hawking’s bestselling book A Brief History of Time (1988). According to Barrow, the Hartle-Hawking model was eventually shown to lead to a universe that was infinitely large and empty i.e. not our one.
The Hartle-Hawking no boundary Hartle and Hawking No-Boundary Proposal

The Hartle-Hawking no boundary Hartle and Hawking No-Boundary Proposal

  • In 1986 Barrow proposed a universe with a past but no beginning because all the paths through time and space would be very large closed loops
  • In 1997 Richard Gott and Li-Xin Li took the eternal inflationary universe postulated above and speculated that some of the branches loop back on themselves, giving birth to themselves
The self-creating universe of J.Richard Gott III and Li-Xin Li

The self-creating universe of J.Richard Gott III and Li-Xin Li

  • In 2001 Justin Khoury, Burt Ovrut, Paul Steinhardt and Neil Turok proposed a variation of the cyclic universe which incorporated strong theory and they called the ‘ekpyrotic’ universe, epkyrotic denoting the fiery flame into which each universe plunges only to be born again in a big bang. The new idea they introduced is that two three-dimensional universes may approach each other by moving through the additional dimensions posited by strong theory. When they collide they set off another big bang. These 3-D universes are called ‘braneworlds’, short for membrane, because they will be very thin
  • If a universe existing in a ‘bubble’ in another dimension ‘close’ to ours had ever impacted on our universe, some calculations indicate it would leave marks in the cosmic background radiation, a stripey effect.
  • In 1998 Andy Albrecht, João Maguijo and Barrow explored what might have happened if the speed of light, the most famous of cosmological constants, had in fact decreased in the first few milliseconds after the bang? There is now an entire suite of theories known as ‘Varying Speed of Light’ cosmologies.
  • Modern ‘String Theory’ only functions if it assumes quite a few more dimensions than the three we are used to. In fact some string theories require there to be more than one dimension of time. If there are really ten or 11 dimensions then, possibly, the ‘constants’ all physicists have taken for granted are only partial aspects of constants which exist in higher dimensions. Possibly, they might change, effectively undermining all of physics.
  • The Lambda-CDM model is a cosmological model in which the universe contains three major components: 1. a cosmological constant denoted by Lambda (Greek Λ) and associated with dark energy; 2. the postulated cold dark matter (abbreviated CDM); 3. ordinary matter. It is frequently referred to as the standard model of Big Bang cosmology because it is the simplest model that provides a reasonably good account of the following properties of the cosmos:
    • the existence and structure of the cosmic microwave background
    • the large-scale structure in the distribution of galaxies
    • the abundances of hydrogen (including deuterium), helium, and lithium
    • the accelerating expansion of the universe observed in the light from distant galaxies and supernovae

He ends with a summary of our existing knowledge, and indicates the deep puzzles which remain, not least the true nature of the ‘dark matter’ which is required to make sense of the expanding universe model. And he ends the whole book with a pithy soundbite. Speaking about the ongoing acceptance of models which posit a ‘multiverse’, in which all manner of other universes may be in existence, but beyond the horizon of where can see, he says:

Copernicus taught us that our planet was not at the centre of the universe. Now we may have to accept that even our universe is not at the centre of the Universe.


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The Origin of the Universe by John D. Barrow (1994)

In the beginning, the universe was an inferno of radiation, too hot for any atoms to survive. In the first few minutes, it cooled enough for the nuclei of the lighter elements to form. Only millions of years later would the cosmos be cool enough for whole atoms to appear, followed soon by simple molecules, and after billions of years by the complex sequence of events that saw the condensation of material into stars and galaxies. Then, with the appearance of stable planetary environments, the complicated products of biochemistry were nurtured, by processes we still do not understand. (The Origin of the Universe, p.xi)

In the late 1980s and into the 1990s science writing became fashionable and popular. A new generation of science writers poured forth a wave of books popularising all aspects of science. The ones I remember fell into two broad categories, evolution and astrophysics. Authors such as Stephen Jay Gould and Edward O. Wilson, Richard Dawkins and Steve Jones (evolution and genetics) and Paul Davies, John Gribbin, John Polkinghorne and, most famously of all, Stephen Hawking, (cosmology and astrophysics) not only wrote best-selling books but cropped up as guests on radio shows and even presented their own TV series.

Early in the 1990s the literary agent John Brockman created a series titled Science Masters in which he commissioned experts across a wide range of the sciences to write short, jargon-free and maths-light introductions to their fields.

This is astrophysicist John D. Barrow’s contribution to the series, a short, clear and mind-blowing introduction to current theory about how our universe began.

The Origin of the Universe

Billions It is now thought the universe is about 13.7 billion years old, the solar system is 4.57 billion years old and the earth is 4.54 billion years old. The oldest surface rocks anywhere on earth are in northwestern Canada near the Great Slave Lake, and are 4.03 billion years. The oldest fossilised bacteria date from 3.48 billion years ago.

Visible universe The visible universe is the part of the universe which light has had time to cross and reach us. If the universe is indeed 13.7 billion years old, and nothing can travel faster than the speed of light (299,792,458 metres per second) then there is, in effect, a ‘horizon’ to what we can see. We can only see the part of the universe which is about 13.7 billion years old. Whether there is any universe beyond our light horizon, and what it looks like, is something we can only speculate about.

Steady state Until the early 20th century philosophers and scientists thought the universe was fixed, static and stable. Even Einstein put into his theory of relativity a factor he named ‘the cosmological constant’, which wasn’t strictly needed, solely in order to make the universe appear static and so conform to contemporary thinking. The idea of this constant was to counteract the attractive force of gravity, in order to ensure his steady state version of the universe didn’t collapse into a big crunch.

Alexander Friedmann It was a young mathematician, Alexander Friedmann, who looked closely at Einstein’s formulae and showed that the cosmological constant was not necessary, not if the universe was expanding; in this case, no hypothetical repelling force would be needed, just the sheer speed of outward expansion. Einstein eventually conceded that including the constant in the formulae of relativity had been a major mistake.

Edwin Hubble In what Barrow calls ‘the greatest discovery of twentieth century science’, the American astronomer Edwin Hubble in the 1920s discovered that distant galaxies are moving away from us, and the further away they are, the faster they are moving, which became known as Hubble’s Law. He established this by noticing the ‘red-shifting’ of frequencies denoting detectable elements in these galaxies i.e. their light frequencies had been altered downwards, as light (and sound and all waves are) when something is moving away from the observer.

Critical divide An argument against the steady-state theory of the universe is that, over time, the gravity of all the objects in it would pull everything together and it would all collapse into one massive clump. Only an initial throwing out of material could counter-act the affect of all that gravity.

So how fast is the universe expanding? Imagine a rate, x. Below that speed, the effect of gravity will eventually overcome the outward acceleration, the universe will slow down, stop expanding and start to contract. Significantly above this speed, x, and the universe would continue flying apart in all directions so quickly that gas clouds, stars, galaxies and planets would never be formed.

As far as we know, the actual acceleration of the universe hovers just around this rate, x – just fast enough to prevent the universe from collapsing, but not too fast for it to be impossible for matter to form. Just the right speed to create the kind of universe we see around us. The name for this threshold is the critical divide.

Starstuff Stars are condensations of matter large enough to create at their centre nuclear reactions. These reactions burn hydrogen into helium for a long, sedate period, as our sun is doing. At the end of their lives stars undergo a crisis, an explosive period of rapid change during which helium is transformed into carbon nitrogen, oxygen, silicon, phosphorus and many of the other, heavier elements. When the ailing star finally explodes as a supernova these elements disperse into space and ultimately find their way into clouds of gas which condense as planets.

Thus every plant, animal and person alive on earth is made out of chemical elements forged in the unthinkable heat of dying stars – which is what Joni Mitchell meant when she sang, ‘We are stardust’.

Heat death A theory that the universe will continue expanding and matter become so attenuated that there are no heat or dynamic inequalities left to fuel thermal reactions i.e. matter ends up smoothly spread throughout space with no reactions happening anywhere. Thermodynamic equilibrium reached at a universal very low temperature. The idea was formulated by William Thomson, Lord Kelvin, in the 1850s who extrapolated from Victorian knowledge of mechanics and heat. 170 years later, updated versions of heat death remain a viable theory for the very long-term future of the universe.

Steady state The ‘steady state’ theory of the universe was developed by astrophysicists Thomas Gold, Hermann Bondi and Fred Hoyle in 1948. They theorised that. although the universe appeared to be expanding it had always existed, the expansion being caused by a steady rate of creation of new matter. This theory was disproved in the mid-1960s by the confirmation of background radiation

Background radiation theorised In the 1940s George Gamow and assistants Alpher and Herman theorised that, if the universe began in a hot dense state way back, there should be evidence, namely a constant layer of background radiation everywhere which, they calculated, would be 5 degrees above absolute zero.

Background radiation proved In the 1960s researchers at Bell Laboratories, calibrating a sensitive radio antenna, noticed a constant background interference to their efforts which seemed to be coming from every direction of the sky. A team from Princeton interpreted this as the expected background radiation and measured it at 2.5 degrees Kelvin. It is called ‘cosmic microwave background radiation’ and is one of the strong proofs for the Big Bang theory. The uniformity of the background radiation was confirmed by observations from NASA’s Cosmic Background Explorer satellite in the early 1990s.

Empty universe There is very little material in the universe. If all the stars and galaxies in the universe were smoothed out into a sea of atoms, there would only be about one atom per cubic meter of space.

Inflation This is a theory developed in 1979 by theoretical physicist Alan Guth – the idea is that the universe didn’t arise from a singularity which exploded and grew at a steady state but instead, in the first milliseconds, underwent a period of hyper-growth, which then calmed back down to ‘normal’ expansion.

The theory has been elaborated and generated numerous variants but is widely accepted because it explains many aspects of the universe we see today – from its large-scale structure to the way it explains how minute quantum fluctuations in this initial microscopic inflationary region, once magnified to cosmic size, became the seeds for the growth of structure in the Universe.

The inflation is currently thought to have taken place from 10−36 seconds after the conjectured Big Bang singularity to sometime between 10−33 or 10−32 seconds after.

Chaotic inflationary universe Proposed by Soviet physicist Andrei Linde in 1983, this is the idea that multiple distinct sections of the very early universe might have experienced inflation at different rates and so have produced a kind of cluster of universes, like bubbles in a bubble bath, except that these bubbles would have to be at least nine billion light years in size in order to produce stable stars. Possibly the conditions in each of the universes created by chaotic inflation could be quite different.

Eternal inflation A logical extension of chaotic inflation is that you not only have multiple regions which undergo inflation at the same time, but you might have sub-regions which undergo inflation at different times – possibly one after the other, in other words maybe there never was a beginning, but this process of successive creations and hyper-inflations has been going on forever and is still going on but beyond our light horizon (which, as mentioned above, only reaches to about 13.7 billion light years away).

Time Is time a fixed and static quality which creates a kind of theatre, an external frame of reference, in which the events of the universe take place, as in the Newtonian view? Or, as per Einstein, is time itself part of the universe, inseparable from the stuff of the universe and can be bent and distorted by forces in the universe? This is why Einstein used the expression ‘spacetime’?

The quantum universe Right back at the very beginning, at 10−43 seconds, the size of the visible universe was smaller than its quantum wavelength — so its entire contents would have been subject to the uncertainty which is the characteristic of quantum physics.

Time is affected by a quantum view of the big bang because, when the universe was still shrunk to a microscopic size, the quantum uncertainty which applied to it might be interpreted as meaning there was no time. That time only ‘crystallised’ out as a separate ‘dimension’ once the universe had expanded to a size where quantum uncertainty no longer dictated.

Some critics of the big bang theory ask, ‘What was there before the big bang?’ to which exponents conventionally reply that there was no ‘before’. Time as we experience it ceased to exist and became part of the initial hyper-energy field.

This quantum interpretation suggests that there in fact was no ‘big bang’ because there was literally no time when it happened.

Traditional visualisations of the big bang show an inverted cone, at the top is the big universe we live in and as you go back in time it narrows to a point – the starting point. Imagine, instead, something more like a round-bottomed sack: there’s a general expansion upwards and outwards but if you penetrate back to the bottom of the sack there is no ‘start’ point.

This theory was most fully worked out by Stephen Hawking and James Hartle.

The Hartle-Hawking no boundary Hartle and Hawking No-Boundary Proposal

Wormholes The book ends with speculations about the possibility that ‘wormholes’ existed in the first few milliseconds, tubes connecting otherwise distant parts of the exploding ball of universe. I understood the pictures of these but couldn’t understand the problems in the quantum theory of the origin which they set out to solve.

And the final section emphasises that everything cosmologists work on relates to the visible universe. It may be that the special conditions of the visible universe which we know about, are only one set of starting conditions which apply to other areas of the universe beyond our knowledge or to other universes. We will never know.

Thoughts

Barrow is an extremely clear and patient explainer. He avoids formulae. Between his prose and the many illustrations I understood most of what he was trying to say, though a number of concepts eluded me.

But the ultimate thing that comes over is his scepticism. Barrow summarises recent attempts to define laws governing the conditions prevailing at the start of the universe by, briefly describing the theories of James Hartle and Stephen Hawking, Alex Vilenkin, and Roger Penrose. But he does so only to go on to emphasise that they are all ‘highly speculative’. They are ‘ideas for ideas’ (p.135).

By the end of the book you get the idea that a very great deal of cosmology is either speculative, or highly speculative. But then half way through he says it’s a distinguishing characteristic of physicists that they can’t stop tinkering – with data, with theories, with ideas and speculations.

So beyond the facts and then the details of the theories he describes, it is insight into this quality in the discipline itself, this restless exploration of new ideas and speculations relating to some of the hardest-to-think-about areas of human knowledge, which is the final flavour the reader is left with.


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The Black Cloud by Fred Hoyle (1957)

‘Nice place you’ve got here. Have some tea?’
‘Thanks, it’s very kind of you.’
‘Not at all.’ (p.95)

If Pierre Boulle’s Monkey Planet is a kind of Swiftian satire which glossed over the practical aspects of space travel in order to concentrate on making its moralising points, The Black Cloud is the exact opposite, a showcase of Anglo-Saxon pragmatism and factual accuracy.

It is set slightly into what was then the future, the narrative opening in January 1964. The blurb on the back has already told you that it’s about a black cloud which enters the solar system heading towards the Earth, so there’s no surprise about the central fact of the story, but any suspense about whether this is going to be an apocalyptic, end-of-the-world shocker is killed stone dead by the first few words of the prologue. This is set fifty years in the future (2020) and immediately establishes the jocular tone and worldview.

It is a humorous letter from a chap at a jolly nice Cambridge college, Dr John McPhail, and he describes the advent of the black cloud as ‘an interesting episode’, so jolly interesting that it was the subject of the thesis which won him his fellowship at Queen’s College, Cambridge. Good show.

So – we realise immediately – the world is not going to end, and also we are going to be dealing with jolly decent chaps from Cambridge and the Royal Astronomical Society. Thus deprived of key elemens of suspense, the interest in this early part of the text derives from:

  • a highly accurate description of the state of astronomical knowledge circa 1957, along with the technology they used then (the different types of telescope, techniques for comparing prints of photos taken of deep space, a long description of punching the tape required in a very early computer)
  • some very detailed calculations about the probable velocity, density and direction of the cloud which the characters do on blackboards as they discuss it, and which are reproduced in the book (you don’t often see extensive mathematical formulae in a novel)
  • some of the terminology and phraseology: I was particularly struck by the way that the word lab, being a contraction of laboratory, is printed as ‘lab.’ throughout

Introduction to the star character, Professor Christopher Kingsley

So a group of astronomers in America notice that something is progressively blotting out stars in a particular part of the sky, while at the same time an amateur astronomer tips off the British Royal Astronomical Society that the orbits of the larger planets in the solar system seem to have shifted. Sceptical experts redo the observations and conclude that something massive is causing them to wobble.

At the meeting where these figures are first discussed we are introduced to the irascible figure of the Cambridge-based theoretical astronomer, Professor Christopher Kingsley, age 37, tall with thick dark hair and ‘astonishing blue eyes’, a man apart, who follows arguments to their logical conclusion no matter how unpopular, who gets cross with anyone slower on the uptake, and manages to be both highly intelligent and a figure of fun to his colleagues – and is without doubt the central character in the book.

All these chaps analyse the findings, draw formulae on blackboards, puff on their pipes and conclude that a cloud of unknown gas is going to engulf the Sun and Earth in about 17 months time. They estimate it will take about a month to transit past, during which time, if it blots out the heat from the sun, most animals on earth will die, along with most humans. Seeds in the soil should survive so the planet’s flora will kick off after the cloud has left.

As in Arthur C. Clarke, the pleasure comes from the scientific accuracy of the speculation at each stage of the narrative i.e. we eavesdrop while the American and British scientists discuss and interpret each new set of data and information as it comes in and then discuss the possible consequences. So one of the pleasures of the book is enjoying the temporary illusion that you are as clever as these top astronomers.

In these early pages Hoyle paints a stark contrast between the cultures of Britain and America. In Britain the astronomer royal visits Cambridge, where it is cold and damp and foggy and depressing – although the college fellows treat themselves to four-course dinners, and then sit by roaring fires drinking vintage wine.

By contrast, when Kingsley flies over to California to meet the astronomers there, he is hosted by astronomer Geoff Marlowe, who takes him for a drive out into the Mojave desert, then to a restaurant where they speculate about the forthcoming world-changing event – then onto a party at a rich property developer’s house, whence Kingsley goes on to a smaller, more intimate party where he tries to dance with a sexy broad, disapproves of American bourbon, doesn’t like the raucous music on the gramophone and generally comes over as an uptight limey. A dark-haired lady offers him a lift back to his hotel, but they go via her apartment where, since she’s forgotten her keys, he helps her break in, and he ends up spending the night

the contrast between big, rich, scenic, partyful and sexually promiscuous America, and cold, foggy, damp, austerity England where there don’t even appear to be any women, let alone loose women, couldn’t be more striking.

The scientists make a base in the Cotswolds

The book is full of what, to the modern reader, seem like all sorts of oddities and eccentricities. The American and British astronomers, over the course of a series of meetings, become convinced that an enormous cloud of gas is heading directly for the sun, though whether it is cold or hot, full of electrical or radioactive activity, or inert, they cannot say. If it’s hot it might boil the earth’s atmosphere way, killing all life. Even if it’s inert it will probably block the light from the sun, as described above, killing nearly all terrestrial life.

There are at least two oddities: one is the way they sit around in their Cambridge rooms, puffing their pipes and offering each other tea and biscuits while they speculate about the likely impact. The other is that both teams decide to conceal the fact from their respective governments. They think politicians will only interfere and cause panic.

In the event news does leak out to the civil service and the Home Secretary comes to meet Kingsley, who, deploying his ‘easy-going, insulting manner’ (p.128) is immensely rude and confrontational, telling him quite openly that he despises politicians and civil servants. We are then party to the Home Secretary reporting back to the Prime Minister and so on. It seems inconceivable that one man’s personal arrogance (Kingsley’s) can influence so much.

In the event a secretary to the PM, Francis Parkinson, comes up with the suggestion that the scientists be given their own research base to study the cloud, and Whitehall settles on the manor of Nortonstowe in the Cotswolds, a nice country mansion which the Ministry of Agriculture had just finished converting into a research centre for agriculture. It is co-opted for the astronomers. Kingsley is their undoubted leader and makes all kinds of demands as rudely as he can of the politicians.

The place us surrounded by military police, and servants rustled up from the nearby new housing estate, while Kingsley rounds up the best minds available and hounds the ministry into installing state of the art telescopes, photography equipment and so on (no computers). Kingsley makes the inexplicable demand that anybody who comes to Nortonstowe will not be allowed to leave. Thus the Whitehall aide, Parkinson, is inveigled into being stuck there, but Kingsley then pulls a deceitful trick by inviting a string quartet he knows from Cambridge to come and perform and, only on the morning after the performance, happening to tell them that, now they’re here, they won’t be able to leave.

Kingsley behaves like a cross between a dictator and a spoilt child and everyone has to put up with it because Hoyle makes him the great genius who knows or calculates or spots or thinks things through far faster than anyone else. The core of the novel is the dynamic between Kingsley and the small court of scientists he has assembled, including:

  • Geoff Marlowe the American
  • British astronomers Dave Weichart and John Marlborough
  • technicians Roger Emerson and Bill Barnett and Yvette Hedelfort
  • the woman leader of the string quartet Ann Halsey (who seems to spend her time making endless pots of coffee for the Big Brains around her and is on the receiving end of some breath-takingly sexist put-downs from Kingsley)
  • Knut Jensen from Norway via the States
  • Harry Leicester from the University of Sydney
  • John McNeil, a young physician, who ends up writing the prologue and epilogue to the narrative
  • and a Russian physicist who happened to be visiting Britain, Alexis Alexandrov, and soon becomes a comic figure because of his habit of speaking in extremely brief, pithy sentences, for example: ‘Gulf Stream goes, gets bloody cold’

Global devastation

Finally the cloud arrives and it is almost as an afterthought to the absorbing conversations between chaps puffing on their pipes and scribbling on blackboards, that Hoyle casually mentions the devastating impact it has on the rest of the human race. They thought the cloud would block the sun and cause a big freeze. They hadn’t anticipated that it would reflect the heat of the sun with increased force. Thus the world experiences unprecedented heatwaves.

Conditions were utterly desperate throughout the tropics as may be judged from the fact that 7,943 species of plants and animals became totally extinct. The survival of Man himself was only possible because of the caves and cellars he was able to dig. Nothing could be done to mitigate the stifling air temperature. The number who perished during this phase is unknown. It can only be said that during all phases together more than seven hundred million persons are known to have lost their lives. (p.120)

The really odd thing about the book, its most striking characteristic, is how the chaps at Nortonstowe carry on discussing theoretical physics and puffing on their pipes through it all. The vast rise in humidity led to atmospheric instability which led to an epidemic of wildly destructive hurricanes around the world. In fact the manor house at Nortonstowe is itself destroyed in one of these hurricanes and one of the astronomers, Jensen, killed.

All this was caused by heat reflected from the cloud. When the cloud itself begins to arrive and blot out the sun’s light and heat temperatures plummet. As Hoyle briskly summarises it:

Except in the heavily industrialised countries, vast legions of people lost their lives during this period. For weeks they had been exposed to well-nigh unbearable heat. Then many had died by flood and storm. With the coming of intense cold, pneumonia became fiercely lethal. Between the beginning of August and the first week of October roughly a quarter of the world’s population died. (p.127)

The scientists notice something strange and ominous. The cloud is slowing down. There is a great deal of scientific speculation about how it could do this which settles on the idea that it is sending out great pellets of ice which are acting like rockets to slow its velocity. Most vivid proof is when one of these enormous ice pellets hits the surface of the moon causing a massive spurt of moon dust which can be observed through earth telescopes. The cloud is slowing down and looks like stopping.

The Prime Minister pays a visit to what’s left of Nortonstowe (where things appear to be carrying on in the same civilised way, with tea and biscuits, despite the house itself having been wrecked) and tells Kingsley he’s pretty cross with the scientists. They said it would only occlude the sun for a month. It’s been there longer. Kingsley gets cross and says that’s because they have no idea what’s going on. Scientists aren’t gods, their knowledge is limited to what is known by observation, the cloud is a completely new phenomenon.

The cloud now does something else unexpected – it changes shape. It slowly changes from being a big amorphous cloud into the shape of a disk. This has the effect of allowing the earth to leave its shadow and emerge back into sunlight. Slowly humanity climbs out of its frozen caves to try and rebuild amid the ruins.

From a pure science point of view what sustains the book is that each stage of the cloud’s progress – from initial sighting through to enveloping the earth – the chorus of scientists Kingsley has assembled at Nortonstowe give voice to every possible interpretation of scientific possibilities. From one perspective the book is like a sequence of seminars on the successive stages of approach and envelopment by a gas cloud, which, altogether, cover a huge range of geographical and terrestrial phenomenon – the scientists discuss the possibility of global warming, global cooling, a new ice age, the atmosphere being heated until it boils, the entire atmosphere being torn away from the earth leaving it barren as the moon, the atmosphere freezing, and so on.

With the cloud now having completely halted and assumed a disc-like shape, and the earth having orbited out of its shadow, the astronomers have to tell the Prime Minister that it might become a new element of life on earth, that twice a year, in February and August, the earth will travel into the cloud and, for a few weeks, lose sun, warmth, life everything. It will be a completely new global condition.

Radio communication

There then follows a lengthy chapter which appears to be going off on a tangent. In preparation for the cloud arriving Kingsley had had the bright idea of installing not just telescopes and so on at Nortonstowe, but an array of the very latest radio equipment. This is because, in the coming disasters, he foresees that a centre of global information will be required. This chapter set out in minute detail the experiments with different wavelengths required to escape the interference caused by the cloud’s upsetting of the atmosphere. But during their experiments a pattern emerges: put simply, every time they change the wavelength, there is ionisation activity at the edge of the earth’s atmosphere which acts to neutralise it.

Kingsley astonishes the chaps by drawing a mad but logical conclusion: the cloud is blocking their radio transmissions; and if it is doing this no matter what wavelength they use, it must contain intelligent life.

Life in the cloud

Then there’s an interesting chapter devoted to the chaps arguing about how the cloud could possibly contain intelligent life and what form it could possibly take. Although Sir Fred Hoyle was the man who coined the expression Big Bang, he did it critically because he himself didn’t believe in the Big Bang theory i.e. that the universe had a definite beginning. Hoyle believed in the Steady State theory i.e. the universe has no beginning and will have no end. This chapter dramatises his theories of how intelligent life might have begun in vast gaseous clouds as electrical activity among groups of crystal molecules which formed on the surface of ice particles.

As routinely, throughout the book, the fact that half the earth’s population has just died, that agriculture and the environment have been devastated, economies ruined, ecosystems destroyed, are all completely ignored while a bunch of chaps sit around having a jolly interesting chat about the possibility of extra-terrestrial life.

Talking to the cloud

They make the decision to send regular pulses into the cloud as signs of intelligent communication. To cut a long story short, the cloud replies and within just a few days they are talking to the cloud. One of the technical johnnies rigs up a system whereby the electronic pulses the cloud sends back can be translated into words via one of those new-fangled televisions and, bingo! They can hear the cloud talk! And he speaks in exactly the tone of a jolly interesting Cambridge academic! This is the first message they hear from the cloud:

Your first transmission came as a surprise, for it is most unusual to find animals with technical skills inhabiting planets, which are in the nature of extreme outposts of life. (p.170)

One of the workers from the housing estate who had tended the gardens and tried to supply the scientists with fruit and veg through all the disasters, was a simple-minded gardener named Joe Stoddard. The technical johnny who rigs up the signals from the Cloud to come through a loudspeaker has, for a joke, used the voice pattern of Joe Stoddard. In other words, mankind’s first communications with the first intelligent extra-terrestrial life it’s encountered are translated into the phraseology of a Cambridge Common Room as expressed through the speech of a Gloucestershire peasant.As a result the scientists unanimously nickname the Cloud, ‘Joe’. Joe says this, Joe says that.

Joe proceeds to tell them all about himself. The universe is eternal and Joe thinks he has existed for some five hundred million years (p.178). He creates units of replicating life and seeds other clouds as he passes. Thus life is spread throughout the universe. He explains that intelligent life on planets is very rare for a multitude of reasons, for example the difficulty o gaining energy from surroundings by processing vegetable matter, and the thickness of skulls required to protect the brain militates against the brain growing in size. Plus the requirement of converting the intangible process of ‘thought’ – in reality a blizzard of electrical signals throughout the brain – into ‘speech’ i.e. the mechanical operation of jaw, lungs, vocal chords etc – a very primitive way to communicate.

This is fascinating and thought-provoking.

The hydrogen bombs

Back in the plot, word gets out to the politicians who are still running the governments of Britain, America and so on, that communication has been established with the Cloud. The governments insist on listening in on a ‘conversation’. This particular conversation is about human reproduction – sex – and its irrationality; it has to be irrational (love, lust) in order to overcome its very obvious pains and risks. The cloud opines that this may be why intelligent life on planets is so rare: the effort required for planet-borne life forms to communicate and to reproduce both tend to emphasise the irrational. Joe thinks the chances are humanity will over-populate the Earth and kill itself off.

After the ‘conversation’ is terminated, the conversation among the scientists continues with a few choice criticisms of politicians everywhere. Then one of the technicians points out that the politicians are still on the line. They have heard the scientists, particularly Kingsley, being as rude and dismissive of political interference as imaginable.

They then get a call from the American secretary of Defence to whom Kingsley is immensely rude and confrontational. When the Secretary threatens Kingsley, Kingsley foolishly replies that he can, with a few suggestions to Joe the Cloud, annihilate America if he wants to.

This seems tactless and rash even for Kingsley and the consequences are bad. As so often happens in 1950s Cold War sci-fi, the American and Russian governments decide the Cloud is a threat to their existence and launch missiles carrying hydrogen bombs at it.

The Nortonstowe scientists learn of this and warn the Cloud who is extremely cross, peeved wouldn’t be too strong a word. Kingsley explains that Earth is ruled by a variety of autonomous governments and that this decision has nothing to do with him or the other scientists. The Cloud announces he will simply return the missiles to their places of origin – with the result that El Paso and Chicago are wiped off the map, along with Kiev. About half a million people are vaporised.

In this, as in the reports of worldwide devastation, the really interesting thing is how offhand and disinterested Hoyle is about these, the melodramatic elements, of his story. Hundreds of millions die, hurricanes destroy the environment, H-bombs destroy American cities… but this is always forgotten whenever the chaps at Nortonstowe make a new discovery about the Cloud.

(And I never understood how Hoyle reconciles the fact that the entire manor house at Nortonstowe is destroyed in a hurricane with the fact that all the scientists carry on meeting in oak-panelled rooms, pouring each other cups of tea, puffing their pipes and discussing the various fascinating problems thrown up by the cloud. Where does all this happen? In a cave?)

The cloud departs

Then Joe the Cloud tells them that another cloud in the vicinity (i.e. hundreds of millions of miles away) has suddenly gone quiet. Joe tells us that this sometimes happens, none of the clouds know why. The clouds themselves are not omniscient. There are many aspects of the universe which are mysteries to them.

In the last few days before the cloud departs, our chaps ask it to tell them more about its vast knowledge. This is a once-in-a-lifetime chance.

‘Now, chaps, this is probably one of our last chances to ask questions. Suppose we make a list of them. Any suggestions?’ (p.204)

Weichart volunteers to sit in front of a series of TV monitors hooked up by Leicester, the TV man, to the Cloud’s wavelength. The transmission begins and vast amounts of information leap across the screens. Slowly Weichart goes into a trance or hypnotised state. His temperature rises, he becomes delirious, he has to be dragged away from the screens to a bed, where he dies.

Then Kingsley announces he will do the same only they’ll ask the Cloud to transmit at a greatly reduced pace. Caring Ann tries to get the other scientists to persuade Kingsley not to do it. Obstinately he insists. He too sits in front of the monitors, his brain is bombarded, he goes into a fugue state, has to be dragged away and sedated. When the sedation wears off he looks deranged and then starts screaming. More sedatives. He dies of brain inflammation. The cloud simply knows too much for a human brain to process, although a couple of the scientists speculate that there might be a subtler reason: it could be that the Cloud not only overloaded his primitive brain with information but that what he learned was so at odds with human understanding, so completely contrary to all the scientific theories which Kingsley had devoted his life to, that he went mad.

Epilogue

A short epilogue explains the end of the affair. It is written by John McNeil fifty years later. He had been co-opted to Nortonstowe as a young physician and was an eye witness to all the key events and discussions. It was he who treated and failed to save Kingsley.

He now explains that the fact that the Cloud was intelligent and the entire course of all its discussions with humans, as well as the fact that it decided to move on out of the solar system, were kept hidden from the public, from the world. A handful of politicians and the tiny cohort in the Cotswolds knew but both decided to keep it secret, for their various reasons.

This text is therefore in the nature of being a bombshell for the human race.

Only now, fifty years later, is he revealing all in this long narrative, addressed to a young colleague of his Blythe. Why Blythe? Well, he’s a fellow academic, but another reason is that he is the grandson of Ann Halsey, the classical musician trapped at Nortonstowe and who – from a few dropped hints – we suspect had an affair with Kingsley while they were confined to the Cotswold mansion. So Blythe is Kinbgsley’s grandson as well (I think).

Now McNeil is leaving Blythe the full narrative of events and leaving it up to him whether to make the whole thing public. He also bequeaths him a copy of the punched card ‘code’ which Kingsley et al used to communicated with the Cloud. What he does with it now is up to him.

Comments

The science is fascinating, and takes on a whole new twist once we realise the cloud is intelligent. But from start to finish what should be appalling, epic events – unprecedented heat wave, blotting out of the sun and unprecedented freeze, death of quarter of the world’s population etc – take a firm back seat to detailed accounts of the conversations between the various chaps, led by the grotesque Kingsley – and these conversations are of such a 1950s, man-from-the-ministry, ornate style that it is really most frightfully difficult to work up the sense of awe or horror a science fiction novel should strive for. Instead one finds oneself more distracted by the Oxbridge and Whitehall Mandarin style of the dialogue than by the epoch-making events the book describes.

This is from the long conversation between secretary to the Prime Minister Parkinson and Sir Charles Kingsley at the latter’s rooms in his Cambridge college. We know they’re getting on because Kingsley offers Parkinson a second cup of tea, puts more logs on the fire, and then makes his demands of the British government thus:

‘I want everything quite clear-cut. First, that I be empowered to recruit the staff to this Nortonstowe place, that I be empowered to offer what salaries I think reasonable, and to use any argument that may seem appropriate other than divulging the real state of things. Second, that there shall be, repeat no, civil servants at Nortonstowe, and that there shall be no political liaison except through yourself.’
‘To what do I owe this exceptional distinction?’
‘To the fact that, although we think differently and serve different masters, we do have sufficient common ground to be able to talk together. This is a rarity not likely to be repeated.’
‘I am indeed flattered.’
‘You mistake me then. I am being as serious as I know how to be. I tell you most solemnly that if I and my gang find any gentlemen of the proscribed variety at Nortonstowe we shall quite literally throw them out of the place. if this is prevented by police action or if the proscribed variety are so dense on the ground that we cannot throw them out, then I warn you with equal solemnity that you will not get one single groat of co-operation from us. If you think I am overstressing this point, then I would say that I am only doing so because I know how extremely foolish politicians can be.’
‘Thank you.’
‘Not at all.’ (pp.83-84)

It’s a little like the end of the world as Ealing Comedy.

‘Would you like to talk to the first intelligent life from outer space that humanity has ever encountered, Charles?’
‘Oh, that’s frightfully kind of you, Algernon, but I was going to make a fresh pot of tea. Why don’t you take first dibs?’
‘Well, that’s jolly decent of you, old chap. Two lumps for me.’


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