Continued from Part 1.

A hundred thousand years had passed since the Big Bang, and the Universe was now made up of atoms, hydrogen and helium, bathed in light the colour of sunlight. This gas was far more diffuse than any earthly gas, only about one atom per cubic metre. It was expanding and cooling fast, and continued to do so for a billion years. The light also cooled, which meant shifting towards red and infra-red. One can imagine angels watching and thinking that this Universe was a failure, as its bright Big Bang was fizzling out like a damp squib. But its Creator had something more in store.

The early Universe, even before atoms were formed, was not as chaotic as it may have looked. It had been remarkably uniform, at least since the end of the very short period of runaway inflation – the same all the way through and in every direction.¹ And on the large scale it still is today.

If the Big Bang had been simply random, then the energy which streamed out from it would have been chaotic and lumpy. Also space and time would not have been the smooth continuum which we see today; they would have been twisted and mixed up, perhaps a bit like an attempt at a balloon model with parts twisted together randomly, blocking the expansion of the Universe. But the space and time we see is more like a normal balloon with a smooth surface, and the Universe can expand freely.

No one knows why the Universe is so smooth, when this in fact seems to be a very special and extremely improbable state of affairs. Maybe it is a result of the little understood early period of inflation. Some people invoke the “anthropic principle”, that the early Universe had to be like this because if it hadn’t been there would be no humans around now to observe it. But surely the hand of God is in this, even though we don’t know how.

For this uniformity of the Universe is of extreme importance today. If the early Universe had been chaotic, it would have remained so, and no kind of structure or order could ever have emerged, at least by natural processes. Either it would have broken up and disappeared into black holes, or it would simply have remained a chaotic mess.²

But the Universe did not remain uniform for ever on the smaller scale. Maybe a billion years after the Big Bang something new became evident. As the atoms continued to move apart and cool they very gradually started to clump together, the weak force of gravity acting on random density fluctuations. Huge masses of hydrogen and helium began to coalesce into the diffuse and swirling clouds which eventually became the galaxies we now observe. Within these clouds smaller regions of gas started to collapse under gravity into the much denser agglomerations which became stars. The original light had been fading for a billion years, but now the Universe was about to be filled again with light.

To be continued …

1. I.e. homogeneous and isotropic. The primary evidence for this is the very high degree of uniformity of the observed cosmic background radiation. This, amazingly enough, is the light released when atoms first formed after the first 100,000 years of the universe, now cooled to less than 3 degrees Kelvin. This evidence of course tells us only about the finite visible part of the infinite Universe, but it is hard to see how this part could be so uniform if the whole is not.

2. This is an attempt to explain how a high entropy Universe would have remained in a high entropy state, and so that the observed low entropy must imply a very special or improbably low entropy initial state.

In the beginning God created the Point. The Point was tiny. It was not quite a mathematical point. But in each of its ten or more dimensions it was wrapped up so tightly that its size¹ was far more than as much smaller than an atom as an atom is smaller than the Solar System.

There was not nothing outside the Point, for there was no outside the Point for nothing to be in. There was just the Point, and the God who created it.

The Point was pulsating with energy, pregnant with possibility, filled with all the intentions of its Creator. Its tiny size could not hold the energy in. It exploded out in a Big Bang, unwrapping three of its dimensions into infinity, becoming the Universe. Energy streamed apart, not out of the Universe for there was no outside, but expanding with the Universe as it became infinite Space.

The Universe began to expand faster and faster. It doubled in size, if you can say that of something which is infinite, perhaps a few hundred times, perhaps even trillions of times, no one knows except God. All this happened in a time so short that it cannot be described in mere words².

For some reason, only God the Creator really knows why, this runaway inflation came to a halt. The Universe continued to expand, but now at a leisurely pace. But still it was so hot, so filled with the energy of God, that no matter could form. All was formless and void. There were no atoms, not even subatomic particles, until the expansion had cooled the universe trillions of times more. Compared with the initial inflation, this gradual expansion took immeasurable ages, but in the units we understand it took perhaps just a millionth of a second to form protons and neutrons, the building blocks of matter as we know it.

The Universe continued to expand and to cool, but it was now changing much more slowly. For millennia it was filled with a plasma, hydrogen and helium nuclei in a sea of loose electrons, like the outer layers of the Sun today. “Suddenly, a hundred thousand years into its unwinding, the skies clear as though on a cloudy summer’s day”, as Peter Atkins puts it³, for, with the temperature now down to ten thousand degrees, electrons stick to nuclei and atoms form. As God said “Let there be light”, the Universe was filled with light, like the light of the Sun today.

Continued in part 2.

NOTE: The above is based on the best ideas of modern physics, as clearly described for popular audiences (in secular terms) in “Galileo’s Finger” by Peter Atkins, Oxford 2003. But some of the details are speculative.

1. I.e. the Planck length, about 10^-35 metres; compare atoms, about 10^-10 m, and the diameter of the Solar System, about 10¹² m.

2. About 10^-32 seconds.

3. p.252.

Note: This is not completely new material. I realised after I posted it that part 3 of this series was rather long, and so I have split it, making the second half of it into this part 4.

In part 3 of this series I discussed the boundary conditions in time, how they might apply to the universe, and how they relate to causality. I also showed how they are in tension with the biblical picture in which God knows and purposes the future, the final state of the universe.

In this post I will look more closely at the final state of the created universe, and how it compares with the initial state.

We observe that the universe is now not in a completely random state but has some order. The Second Law of Thermodynamics implies that its initial state was even less random, technically with lower entropy than at present. It also implies that the final state of the universe will be more random, with higher entropy.

Cosmologists have observed that the background radiation which they interpret as being left over from the Big Bang is extremely uniform across the sky. This implies that at least from an extremely early stage, if not from the very beginning, the universe expanded isotropically, i.e. in the same way in all directions, to a very high degree of accuracy. This isotropy implies order and low entropy; the very early universe was not in a random state but in an extremely special one. Theologians might see the hand of God in this; cosmologists have sought to explain it with physics, but in a way which would require that the Second Law of Thermodynamics did not apply in the first fraction of a second (actually only something like 10^-32 seconds in some expansion theories) after the Big Bang.

My argument here is not in fact at all dependent on the Big Bang theory. It would work equally well if the universe was created in a form similar to its present one, even as recently as 4004 BC. But its initial state, at least once the act of creation was complete and the normal laws of physics took over, must have been not completely random, but with order and so low entropy. It first came into being “formless and empty” (Genesis 1:2 TNIV), Hebrew tohu wabohu; these words may imply a state of chaos, but if so God created order within it during his work of creation before putting it in “bondage to decay” (Romans 8:21 TNIV).

As for the final state of the universe, cosmologists generally assume that it will be highly disordered. According to them, there are two possibilities: either the universe will continue to expand for ever but will gradually become more and more disordered, with entropy eventually approaching a maximum, the so called Heat Death; or the universe will collapse again into a Big Crunch, which, according to most, will be very different from the Big Bang in that it will be highly disordered and anisotropic, a state of high entropy. Both Heat Death and a disordered Big Crunch can be considered as unconstrained; there are no final boundary conditions here.

However, some cosmologists have speculated that at some time in the future, probably at about the time that the universe reaches its maximum size, the Second Law of Thermodynamics will go into reverse, and that entropy will start to decrease, such that the universe will collapse in an isotropic Big Crunch which will look just like the Big Bang in reverse. Thus the history of the universe will be at least in general terms symmetric in time. But these cosmologists have realised, without as far as I know discussing this in detail, that such a reversal of the Second Law would have complex and severe philosophical implications, and for this reason the idea is not a popular one.

Nevertheless, they have an interesting idea which is helpful to illustrate the direction in which I am arguing here. In the standard cosmological model, there are tight boundary conditions on the initial state of the universe, constraining it to be isotropic, so in a state of order and low entropy; but there are no final boundary conditions, as required by the principle of causality, implying that the final state is disordered. But if there will also be an isotropic Big Crunch, that is a final and tightly constraining boundary condition. Now as I have tried to make clear, there is only one law of physics which disallows this, the Second Law of Thermodynamics, and that applies only because of causality. An isotropic Big Crunch is possible only if causality does not apply completely, that is, if at least in principle current events can be caused by future ones, indeed ultimately by the Big Crunch itself.

According to cosmologists, the universe is still expanding, and it will be a very long time before it starts to contract again towards a Big Crunch, if it ever does. So, in the isotropic Big Crunch model, its current state is like a point on the banner quite near to one of the poles, or the distribution of the children soon after they were released and before they were starting to think about going home. That is to say, the universe is still quite tightly constrained by its initial boundary condition, the isotropic Big Bang, but the constraints of the final boundary, the Big Crunch, so far have only a very weak effect. Because of this the universe now operates almost precisely as if there were no final constraints, and so according to causality and the Second Law of Thermodynamics. Nevertheless, if there is going to be an isotropic Big Crunch, one might expect to see very occasional or very tiny deviations from this law, which will gradually grow as the universe moves towards the mid-point of its life. Then it will have a severe mid-life crisis! I will not presume to speculate on how physics will operate around this time. But eventually the Second Law will gradually start to work in reverse as the universe collapses towards the Big Crunch.

Now it is interesting to speculate about this time-symmetric universe. But actually I don’t think this is what is going to happen. If the Bible teaches us anything about the final boundary conditions for the universe, those conditions are not an isotropic Big Crunch, but some kind of steady state for eternity. It is interesting that scientists are still unable to decide whether the universe will continue to expand indefinitely or collapse in a Big Crunch. A third and intermediate position may be possible, in which it grows to a fixed size and remains that size for ever; and the current expansion of the universe is at about the right rate to attain this. This steady state is probably a very special and improbable state, similar to the isotropic Big Crunch, but if it is a final boundary condition specified from the beginning, the universe is bound to end up in this state. But if there is such a final boundary condition, causality and the Second Law lose their absolute status, and at some stage will gradually cease to operate.

I have to accept that these ideas, especially the final one, are highly speculative. But I hope you find them interesting.

In the next part of this series I intend to relate these ideas to the coming of the Kingdom of God. I hope there will be less heavy physics and more about God and the Bible.

Note re links to Wikipedia: I provide these as service to readers wanting to read a little more about the subjects in question, not as authorities or references.

In the Introduction to this series I explained my long-standing fascination with the Second Law of Thermodynamics and how it relates to Christian teaching, especially to Romans 8:19-23. I wrote about how I had been thinking about these matters on and off for about 30 years.

In particular I remember sitting in the Cavendish Laboratory library in Cambridge, in 1976 or 1977, looking at some rather heavy books dealing with the theoretical basis of the Second Law. While I don’t remember the names of the books, I do remember the basic point I discovered: the Second Law is not dependent on experimental evidence, for it can be deduced by pure logic. It must be this that gave Arthur Eddington such supreme confidence in this Law that he could write:

if your theory is found to be against the second law of thermodynamics I can give you no hope; there is nothing for it but to collapse in deepest humiliation.

But what I did not find in the books I consulted was a recognition of a hidden assumption in the logic. Yet it should in fact be rather obvious that there is some such hidden assumption, for without it there is no way that the time asymmetry of the Second Law can arise, within a framework of more fundamental laws which are all time-invariant.

The hidden assumption on which the Second Law of Thermodynamics is based is causality. That is to say, it is assumed that any event in the universe is caused solely and completely by other events in the universe which precede it in time, but cannot be caused or affected by any event which follows it in time.

To most people in the modern world this principle of causality seems so obvious that it can be assumed without question. This was certainly not always the case. And I will go on to argue here that there is a fundamental contradiction between causality and Christian teaching.

Nevertheless I must recognise that in practice the world in which we live operates according to the principle of causality. It is perhaps this rather than the Second Law of Thermodynamics which explains why we don’t see stationary objects suddenly start to move without an cause or applied force. If the principle of causality needs any experimental proof, it is in the precise and predictable way in which even at the sub-microscopic level physical, chemical and biological systems obey the Second Law. And we should be glad of this, for without this neither our modern technology nor our bodies would function.

But the principle of causality has implications which conflict with Christian theology. Causality implies that what happens now depends only on what has happened in the past within the universe. The Bible teaches that what happens now is preparation for the future consummation, that “The creation waits in eager expectation for the children of God to be revealed” (Romans 8:19, TNIV) and “all things work together for good to those who love God” (Romans 8:28, TNIV marginal reading).

Now it is not a violation of causality for an event now to be preparation for a future event, if it is caused by an intelligent being who is planning for that future event. In this sense we might be able to argue that current events which are God’s preparation for the future are caused by God, and so preserve the principle of causality. But this resolution only works if we place God within the universe, and his plans for the future within time – specifically, in the distant past. Some theologians (associated with Process Theology and Open Theism, from the limited amount I know about these movements) have taught that God is inside the universe and constrained by time, and in this way they could preserve the principle of causality. However, this view of God has not been accepted by most theologians, for the good reason that it seems to conflict with the biblical picture of God as separate from his created universe and not constrained by time or space.

If God is outside of the universe, an event caused by him has a cause from outside the universe, in contradiction to the principle of causality. Also, from a theological viewpoint all events are part of God’s preparation for the future and must therefore be at least in part caused by God. So all events have a cause outside the universe, and there is nothing left to be caused according to the normal principle of causality operating within the universe. Thus the classic view of God as outside time and separate from his creation is incompatible with the principle of causality.

But why then do we see the universe operating on the basis of causality and according to the Second Law of Thermodynamics? The answer was clearly written by the Apostle Paul: “the creation was subjected to frustration, not by its own choice, but by the will of the one who subjected it” (Romans 8:20, TNIV). In other words, the universe is currently experiencing “frustration” and “bondage to decay” through the operation of the Second Law because God has chosen to let it work for the time being according to the principle of causality. But, Paul promises, this will not always be true, for we and all creation can look forward in hope to the time when “the creation itself will be liberated from its bondage to decay and brought into the freedom and glory of the children of God” (Romans 8:21, TNIV).

In this verse Paul writes of this as something entirely in the future. But elsewhere, even in this chapter, he suggests that this “freedom and glory of the children of God” is something not entirely future, but which is already starting to appear among Christian believers:

¹⁴ For those who are led by the Spirit of God are the children of God. ¹⁵ The Spirit you received does not make you slaves, so that you live in fear again; rather, the Spirit you received brought about your adoption to sonship. And by him we cry, “Abba, Father.”

(Romans 8:14-15, TNIV)

Not only so, but we ourselves, who have the firstfruits of the Spirit, groan inwardly as we wait eagerly for our adoption, the redemption of our bodies.

(Romans 8:23, TNIV)

In other words, as Christians we have already been adopted as children of God and given the Holy Spirit, and so in principle we already have “the freedom and glory of the children of God”. But we live within a universe which remains in bondage to decay; even our bodies are in bondage to decay working within them as they operate. Yet the promised freedom of the Kingdom of God has already broken through into our lives, and continues to break through, through us, into the world around us.

So, while we can expect the world and our bodies to continue to follow the principle of causality and the Second Law of Thermodynamics, as Christians we should not expect to be bound by this principle and this law. In the spiritual realm we are not bound by them. And, as I will go on to explain in further parts of this series, we should expect to see times and places where these rules are not followed even in the physical realm, because the Kingdom of God is breaking through into the world.

But this is enough for this posting. More will follow. In the next part I look at “boundary conditions” of the universe.

Meanwhile, does anyone reading this know of any specialist forums, journals etc where issues like this are discussed? If so, please let me know by commenting on this.

I should start this series of posts by suggesting that perhaps it does not really belong at Speaker of Truth. For I cannot presume to call what I intend to write here, at least after this introduction, “truth”. I hope that it is an exploration in the direction of truth, but some might prefer to write it off as “speculation”. On the one hand, these are preliminary thoughts on this subject, and are liable to be refined at any time. On the other hand, although this is, I think, the first time I have gone public on this, I have already been thinking it over on and off for about 30 years. Yes, really: I remember doing some research on this when I was a student in Cambridge, it must have been 1976 or 1977, in the library of the Cavendish Laboratory.

As a student of physics at that time, and as a young Christian, I was fascinated by time, and I still am. I learned that almost all of the fundamental laws of physics are time-invariant, that is to say, they work exactly the same when time is reversed. If you watch a film which only shows things operating according to these laws, you cannot tell whether it is being played forwards or backwards. This applies, approximately, to such things as swinging pendulums and heavy objects travelling through the air; it also applies, perfectly, to all process on the atomic scale (technically, if charge and parity are also reversed).

There is just one fundamental law of physics which is not time-invariant: the Second Law of Thermodynamics. This law in its most basic form states that the entropy of a system always increases, which means that the system gradually become more disordered. This may explain the state of my desk! It also explains why heat always flows from hotter to colder bodies, and why moving objects, unless in a vacuum, slow down and stop unless a force is applied to keep them moving. These are all processes which are not time-invariant; if you see a film which shows systems spontaneously becoming more ordered, heat flowing from colder bodies to hotter, or moving objects speeding up without a force, you quickly realise that it is being played backwards.

On the face of it this law, that systems will always become more disordered and will tend towards a state of uniform temperature and only random motion, might seem to be a rather negative and useless one. However, biological systems are able to make use of this law to produce effects which seem to contradict it – but do not really do so, for an organism can decrease entropy in one place only by increasing it even more in other places, typically by converting low entropy food into high entropy waste products. Similarly, human ingenuity has contrived various kinds of engines, which are basically methods of creating ordered motion by converting low entropy fuel into high entropy exhaust gases; thus the modern human world can continue its activities by generating huge amounts of waste entropy which (to grossly oversimplify some very complex processes and issues) causes global warming.

There is something rather special about the Second Law of Thermodynamics which goes beyond its breaking of time invariance. The early 20th century physicist Arthur Eddington wrote:

The second law of thermodynamics holds, I think, the supreme position among the laws of Nature. If someone points out to you that your pet theory of the universe is in disagreement with Maxwell’s equations – then so much the worse for Maxwell’s equations. If it is found to be contradicted by observation, well, these experimentalists do bungle things sometimes. But if your theory is found to be against the second law of thermodynamics I can give you no hope; there is nothing for it but to collapse in deepest humiliation.

What made Eddington so sure of his ground on this one? I am sure that it was not just that the Law fitted so precisely with observation. Eddington’s own greatest claim to fame is that he was the first to confirm Einstein’s General Theory of Relativity by detecting a small deviation from Newton’s laws. But he did not seem to allow that there might be even such tiny deviations from the Second Law of Thermodynamics. The reason for this seems to be that, in addition to the experimental evidence, there is a fundamental philosophical and logical basis to the Second Law. It was this basis that I was researching at the Cavendish Laboratory, where Eddington had studied before me.

But my interest in this issue was sparked all those years ago not so much by the physics involved as by what is taught in the Bible. I read (at that time not in this version) and thought about the following:

¹⁹ The creation waits in eager expectation for the children of God to be revealed. ²⁰ For the creation was subjected to frustration, not by its own choice, but by the will of the one who subjected it, in hope ²¹ that the creation itself will be liberated from its bondage to decay and brought into the freedom and glory of the children of God.

²² We know that the whole creation has been groaning as in the pains of childbirth right up to the present time. ²³ Not only so, but we ourselves, who have the firstfruits of the Spirit, groan inwardly as we wait eagerly for our adoption, the redemption of our bodies.

(Romans 8:19-23, TNIV)

These verses fascinated me. The Apostle Paul wrote that “the creation was subjected to frustration… [in] bondage to decay”, and he was writing 1800 years before physicists formulated the same principles as the Second Law of Thermodynamics. But, whereas for physicists like Eddington the Second Law is absolute and immutable, Paul wrote that this “bondage to decay” is ordained by God as something temporary, from which it can eagerly expect liberation.

But how could I, as a physicist at the time and later as a student of theology, bring together these two opposing viewpoints on the same phenomenon? What is the philosophical basis of the Second Law of Thermodynamics, and how does this compare with Christian teaching? Could the differences here be linked to the “problem” of miracles, events which seemed to break the laws of physics? And how does it all relate to the coming of the Kingdom of God and our hope of experiencing “the freedom and glory of the children of God”? I hope to deal with these matters in future posts. But I am posting this introduction without having written any more, so don’t expect the rest of the series very quickly!

Update: see part 2: Beyond Causality; part 3: The Boundaries; part 4: The Crunch.