The Doctrine of Creation (part 11)November 08, 2008 Time: 00:45:47
We’ve been talking about the doctrine of creation for the last several months. We have looked at philosophical arguments for creation. We then began to look at scientific confirmation of the doctrine of creation. You will remember I shared that on the standard Big Bang model, which was first broached back in the 1920s as a result of a cosmological application of Einstein’s General Theory of Relativity, that if we let this disc represent the three dimensions of space (suppressing one dimension because we are going to be trying to portray a three-dimensional object here on this space) according to the standard model as you go back in time space shrinks down until you finally come to an initial cosmological singularity or beginning point which is the boundary of space and time itself before which nothing existed. All matter and energy, indeed space and time themselves (at least as physics understands them), come into being at the initial cosmological singularity.
This supports or provides dramatic empirical confirmation of the biblical doctrine of creation ex nihilo – creation out of nothing. It is amazing that modern science some twenty or more centuries after the time of Christ and the time of the Bible should be discovering evidence that supports the biblical doctrine of creation out of nothing. But many scientists were not happy with the idea that the universe began to exist out of nothing. Since the model was proposed one theory after another has been proposed in an attempt to avert the prediction of the standard model of an absolute beginning of the universe. I thought we would run through some of these briefly to chart the confirmation of the standard theory that has occurred.
The first alternative to the standard Big Bang model was the Steady State theory broached in 1948 by Fred Hoyle and Thomas Gold. According to this model of the universe, the universe is expanding all right – so if we let these dots represent galaxies in outer space, they are receding from one another just as the standard model predicts. But according to the Steady State model when the galaxies recede from one another new matter comes into being out of nothing to replace the matter that has receded. So over time the universe never changes. The universe is expanding, yes. But its appearance never changes because as the galaxies recede from one another new matter comes into being and takes the place that used to be there.
On such a theory, if you go back in time the universe doesn’t grow any denser because as the galaxies approach each other they just vanish. The matter just goes into non-being. It just disappears. On this model, you never have an absolute beginning of the universe, but you do have the constant creation of matter and energy out of nothing all the time! In fact, one of the alternative names for the Steady State theory is Continuous Creation. It is a continuous creation model of the universe, but it doesn’t have an absolute beginning.
The Steady State theory never secured a single piece of experimental verification. It was always trying to explain away the facts rather than to make predictions that could then be verified. It never explained any experimental predictions that the theory uniquely made. A further strike against the model was that observations of galaxies further and further out showed that, in fact, there were more radio galaxies in the past than there are today. Therefore it showed that the universe has not been in a steady state after all. Rather the universe has evidently an evolutionary history in which the type of structures in the universe have changed over time. But the real nails in the coffin for the Steady State theory came in 1965 when two scientists working for the Bell Telephone Laboratories – A. A. Penzias and R. W. Wilson – discovered by accident a microwave background radiation which had been predicted back in the 1940s by George Gamow on the basis of the standard Big Bang model. Gamow predicted that if the universe is expanding from a big bang that pervading the entire universe should be this background of low temperature radiation that fills the entire universe. This background radiation is a microwave radiation. It is the same kind of radiation that is in your microwave oven at home. This microwave radiation was discovered accidentally in 1965 by Penzias and Wilson. This microwave background radiation is a vestige of a very hot and very dense state of the early universe. Since on the Steady State theory no such condition ever existed, the Steady State model has been abandoned by everyone. The discovery of the microwave background radiation effectively killed the Steady State theory.
Dr. Craig: I don’t think that is microwave radiation, but it would illustrate quantum indeterminacy. It is true that the kind of fuzz you get would be an illustration of the kind of indeterminacy that exists on the subatomic level. But that wouldn’t be relevant to this, I think.
Dr. Craig: In one sense there aren’t any outer limits. The universe could be infinite in extent like a big rubber sheet, like, say, a wrestling mat that has spots painted on it or buttons glued to it. Or it could be like the surface of a balloon. A surface of a balloon has no edge – you just keep going around and around. The universe could be finite or it could be infinite. As the rubber is stretched or as the balloon is inflated then these things grow farther apart from each other. The idea is that new stuff comes into being. The odd thing about this model is that it is in complete contradiction to the laws of thermodynamics which says that energy is neither created nor destroyed. In fact, it would show that the universe is not a closed system. It would violate the second law because energy would be constantly being fed into the universe which is paradoxical. The model was really bizarre right from the beginning. It just shows the determination of certain theorists to avoid the idea of an absolute beginning. Hoyle was openly anti-theological in his motivations to avoid an absolute beginning of the universe and an initial point of creation, even to the extent of doing this.
Let me go on to the next model in the interest of time.
During the 1960s, a new attempt to avoid the absolute beginning of the universe predicted by the standard model became popular – these were oscillating theories of the universe. The standard Big Bang model is based upon the assumptions of homogeneity (which means that matter is evenly distributed on large scales throughout the universe; matter is homogeneous throughout the universe on very large scales), and isotropy. That is kind of a neat word that you don’t hear very often. Isotropy means that it is the same in all directions. No matter which direction you take, it won’t matter. The universe will be the same in whatever direction you take. The standard Big Bang model was based upon the assumptions of homogeneity and isotropy of the universe and of matter distribution in it. During the 1960s certain theorists, particularly Russian cosmologists, in an attempt to avoid the beginning of the universe hypothesized that if the universe is not perfectly homogeneous and isotropic then if we run the expansion back in time so that the matter approaches one another then if the universe is not perfectly homogeneous and isotropic maybe some of this matter wouldn’t coalesce to a point but it would pass by itself so that the universe would appear to bounce back to a new expansion. The universe would be kind of like an accordion contracting and then expanding and then contracting and then expanding from eternity so that you get a kind of oscillating model of the universe. If we have a diagram on which we let the vertical axis represent the radius of the universe and the horizontal axis be time the universe would appear to be cyclical. If this could be extended into the infinite future as well as into the infinite past then the absolute beginning of the universe might be avoided.
Again, this theory was enormously conjectural. There was never any evidence or even any physics that would explain how this might happen. The prospects for the oscillating model were severely dimmed in 1970 by Roger Penrose and Stephen Hawking’s discovery of the singularity theorems that bear their names. The Hawking-Penrose singularity theorem disclosed that under very generalized conditions that any object which is in a state of gravitational self-collapse (it is contracting upon itself) will contract down to a singularity. Therefore, whether the universe is homogeneous and isotropic or not doesn’t really matter. Even if the universe is inhomogeneous and non-isotropic it will still contract down to a singularity. It will not bounce back as was hypothesized.
Moreover, the thermodynamic properties of an oscillating model revealed something very interesting. What was discovered is thermodynamically what is called entropy is preserved or conserved from cycle to cycle. Entropy is a measure of the unusable energy of a system. Entropy always increases in a closed system. As the system tends toward a state of equilibrium the processes tend to run down and quit. This is because of the increase in entropy – this unusable energy. What was discovered is that the entropy would be conserved from cycle to cycle. It wouldn’t be annihilated. And, moreover, the effect of this entropy increase is to enlarge each cycle’s radius and each cycle’s expansion time. So the universe would, in fact, oscillate like this [Dr. Craig draws a diagram on the whiteboard.] What that means is as you trace the oscillations back in time, they get smaller and smaller until you finally come to a first oscillation and a beginning of the universe. So in the words of one scientific team, the oscillating model has an infinite future but only a finite past. In fact, the astronomer Joseph Silk in his book The Big Bang estimates on the basis of current entropy levels in the universe, the universe could not have gone through more than one hundred previous oscillations.
There are other problems with the oscillating model as well. Let me just mention one. The most recent measurements on supernovae – these stellar explosions in far, far distant outer space – indicate that rather than slowing down, the expansion of the universe is actually speeding up. Contrary to all expectations, the universe is not slowing down from the internal pull of its own gravity, there is some kind of anti-gravity force that kicks in and actually causes the expansion to accelerate. The question of the oscillating universe becomes even more difficult because even if the universe is very dense and has strong internal gravitational pull this is overcome by what is called the cosmological constant which is this sort of anti-gravity force that kicks in and causes the expansion of the universe to actually accelerate which makes all the more difficult the notion of an ultimate re-contraction.
Dr. Craig: I said that as you trace the expansions back in time, the oscillations get smaller and smaller until you finally come to a beginning.
Dr. Craig: I may have said (I’m not sure) that therefore the model implies the very beginning of the universe that its proponents sought to avoid. If I didn’t say that, I do say that.
Dr. Craig: I am not familiar with that. I don’t know. What I do know is that the Hawking-Penrose singularity theorems imply that there is going to be a singularity at some point in the finite past which will be a boundary to space and time. There are all different kinds of singularities. They don’t all take the same form or shape. There are pancake singularities; there are point-like singularities. There is a broad variety. Perhaps this is one type that you’ve mentioned where you would have this sort of geometry to it. But the common characteristic of all singularities is that they constitute boundary points to space and time. That is the key point here. The universe won’t bounce back before it hits the singularity. Once it hits the singularity nothing can pass through a singularity because it is a boundary point to space and time. It is the end of space and time.
These oscillating models, even though there was no evidence for them and these severe problems against them, exhibited a very stubborn persistence because, I think, of the metaphysical appeal they had to certain theorists in avoiding the absolute beginning of the universe. But as soon as another theory came along trying to offer the same advantage, the oscillating models sunk into oblivion. The models that came along in the 1970s might be called vacuum fluctuation models. In 1973 a scientist by the name of Edward Tryon suggested that perhaps the universe is a fluctuation that happens by accident in a kind of broader vacuum space. On the subatomic level, these sorts of fluctuations are said to take place all the time. He imagines that there is this sort of wider empty space which is just a vacuum but in physics a vacuum doesn’t mean what a layman means by a vacuum – namely, nothing. Whereas in physics, the vacuum is a sea of fluctuating energy. It is not really empty at all. It is an arena of violent activity on the subatomic level – energy constantly fluctuating, forming little particles that then dissolve back into the energy of the vacuum again. What Tryon suggested was maybe the universe is one of these particles that instead of dissolving back into the energy of the vacuum, it somehow continued to live on. If we imagine this to represent the corner of a box – like a big empty box that is a vacuum – there are fluctuates that occur and some of these will grow into expanding universes within the womb of this wider vacuum. [Dr. Craig draws an illustration on the whiteboard.] Therefore our universe is just a mini-universe within the womb of this wider universe as a whole. The expansion that we observe is not the absolute beginning of the universe; it is just the beginning of our universe within the womb of this wider quantum mechanical vacuum which is conceived itself to be eternal and beginningless.
Again, this was an extraordinarily speculative theory – to think the universe might be a long-lived subatomic particle. But the fundamental flaw in these models as was pointed out by Christopher Isham, who is a quantum cosmologist at London’s Imperial College of Science and Technology, is that at any point in this wider vacuum space there is a non-zero (that is to say, a positive probability) of a fluctuation occurring that would form into a universe. What that means is that given infinite past time there will have occurred fluctuations at every point in the quantum vacuum which would turn into universes. So these would have now begun to collide with each other and fill all of the quantum mechanical background space so that we should be observing an infinitely old universe. The only way to avoid this contradiction would be to postulate an expansion of the background space itself so that these are moving away from each other so that they won’t collide. But then of course all you’ve done is pushed the problem back a notch because now if the vacuum space is expanding, that will shrink back to an initial beginning point and nothing is solved. Therefore, these vacuum fluctuation models, again, really didn’t generate a whole lot of following and were discarded around twenty years or so ago.
Dr. Craig: Right, universe. Because all these little universes would have coalesced together and filled up this infinitely old vacuum space. So we wouldn’t be observing a relatively young universe. We would see an infinitely old universe, which contradicts observation.
Dr. Craig: Very clever response! One theorist – J. Richard Gott – in an article I saw tried to get around this problem by saying maybe this vacuum space is infinite in size and the fluctuations only occur infinitely far apart. Well, such a move is totally ad hoc. This is a quantum mechanical vacuum. As I say, at every point in the vacuum there is a positive probability that in time a fluctuation will form that will turn into a universe. It is completely ad hoc – that means contrived or artificial – to lay down this sort of rule: quantum fluctuations can only occur at infinite distances from each other. But even if you granted that, think about it. Given infinite past time, each one of those infinite regions would have been filled by now. Therefore, the whole quantum mechanical vacuum space would have been filled by now and you’d have the same conclusion. We should be observing an infinitely old universe. So even given Gott’s ad hoc or contrived hypothesis, it doesn’t solve the problem once you have an infinite past. The only way to get around it would be, as I say, to postulate an expansion of the background space itself so as to keep these things moving apart. But then you are just right back out of the frying pan into the fire again.
Let me go to the next model which has been broached. This is a form of inflationary theory. What is inflation? Inflation is an adjustment to the standard theory that probably most cosmologists today would want to make. According to inflation, at the very early history of the universe – say, right after the Big Bang – the universe underwent a period of super-rapid or inflationary expansion during which its size blew up from a subatomic particle about the size of a grapefruit. Then it settled down to its more leisurely expansion that we observe today. So the universe would look something like this. [Dr. Craig draws an illustration on the board.] This inflationary period occurs between about 10-35 and 10-33 seconds after the Big Bang – just an infinitesimal moment during which the universe inflates in this way.
In most inflationary models, as you see, prior to the period of inflation the universe continues to shrink back down to the initial singularity and the absolute beginning of time. But some theorists are troubled with the idea that the universe has an absolute beginning in that way. Some have tried to use inflation as a means of avoiding the initial cosmological singularity. One theorists who has been an especially creative thinker on this is the Russian cosmologist Andrei Linde. Linde champions what he calls chaotic inflationary theory. On chaotic inflationary theory, inflation never comes to an end. Rather, every domain of the universe when it reaches a certain size spawns more inflation. So rather than being like a balloon blowing up, the universe is more like a balloon with ears, and these ears then sprout other ears, and so on ad infinitum. Inflation just keeps going on and on forever. Linde says such a model would have an infinite future. But he is troubled of the idea of an absolute beginning. He says this raises the philosophical problem of where did the universe come from if it had a beginning. He suggests maybe inflation can be extended infinitely into the past. Every domain that we see is the product of some prior domain. So just as inflation goes on in the future forever, it has gone on from infinite time in the past. In that way you avoid an absolute beginning of the universe and the creation of the universe.
In 1994, however, two other cosmologists – Arvind Borde and another fellow Russian cosmologist Alexander Vilenkin – developed a theorem by which they were able to show that any universe which is inflating eternally toward the future cannot be infinite in the past. Rather, any future eternal inflationary universe must have at some point in the indefinite past a beginning singularity – a beginning point. Therefore they say this forces us to address the metaphysical question of “Where did the universe come from? Why does it exist?” In response to Borde and Vilenkin’s theorem, Linde threw in the towel and admitted, yes indeed, you are correct – even an inflationary theory must have an absolute beginning point. In the year 2001 and again in 2003 Vilenkin and Borde in cooperation with Alan Guth (the father of inflationary cosmology) were able to strengthen their theorem to show that any universe which has on average been expanding throughout its history must have an initial boundary point in the past. This really put the nix on any attempt to extend these constantly expanding universes infinitely into the past. There must be a beginning point.
Dr. Craig: He asked if this is like fractals. It is not really the same thing. I can appreciate why you would say that in that you kind of have the complexity within complexity within complexity. But this is more an evolutionary theory. It is as space reaches a certain volume, this inflation kicks in and new domains are generated by the inflation of space. It has the same infinite quality I guess, but it is quite different than the mathematical theory of fractals.
Vilenkin and Borde at the end of their article criticizing Linde’s chaotic inflationary model say that the best way to deal with his metaphysical question is by developing a quantum theory of gravity to explain the origin of the universe. This would be an attempt to unite Einstein’s General Theory of Relativity (which is a theory of gravitation) with quantum theory in order to get a quantum theory of gravity. These two pillars of contemporary physics have yet to be unified with each other. It is at though modern physics stands upon two great pillars – General Theory of Relativity and quantum theory. And yet nobody knows how to put these together for certain. In these models it is suggested that if we could develop a quantum theory of gravity this would help to perhaps eliminate the initial cosmological singularity. The most celebrated of these theories in the popular press has been Stephen Hawking’s proposal.
On Hawking’s proposal, as you go back in time and space shrinks down you don’t come to an initial cosmological singularity. Rather, the initial part of the universe is rounded off so that the universe is not like an inverted cone that begins in a point; rather, it is more like a badminton birdie that has a rounded sort of hemisphere on the bottom. Therefore, there is no boundary point or beginning point to the universe. The space-time is rounded off. Far from denying the creation of the universe, however, I think these models actually support the creation of the universe and its absolute beginning. On these models, you’ll notice the past is finite. There is no point earlier than this. It has a closed geometrical surface, not an open surface like a plane. And it is a finite time ago. These models actually support the beginning of the universe. The only difference between them and the standard model is that they do not begin to exist in a point in which you have infinite density, infinite temperature, infinite pressure, and so forth. They have a beginning, but they don’t have a beginning point. But you see, having a beginning doesn’t entail having a beginning point. Something can begin to exist even if it doesn’t have a beginning point. The past in particular has a beginning if for any interval of time you pick (say, an hour) . . . if prior to that hour there are only a finite number of equal intervals then time began to exist. Whether there is a first instant or not is irrelevant. On this model there isn’t a beginning point which is a singularity, but the universe still has a beginning and therefore is still created out of nothing.
One further point that is worth making about these models. This rounding off of space-time is achieved by using imaginary numbers for the time coordinate. Imaginary numbers are numbers which are multiples of the square root of -1. When you think about it, there is no real number when it is squared gives you a negative number. Any real number squared will always give you a positive number. So there aren’t any real numbers that are the square root of -1 or multiples thereof. These are called imaginary numbers. What Hawking does is he uses these imaginary numbers as the value for his time coordinate. By doing that it effectively makes time and space indistinguishable. The problem is the use of imaginary numbers is just a sort of mathematical trick or reckoning device to make the equations doable. But when you get to the end result of your equations, you are always supposed to convert back into real numbers to get a physically significant result. Otherwise, it is meaningless. For example, if I were to tell my wife today what the imaginary attendance was in Sunday School, it makes no sense. Or what is the imaginary volume of this room? These are physically meaningless notions. Similarly, the idea of imaginary time (2 imaginary seconds, say) is a physically meaningless notion. So you always need to convert back to real numbers. Here comes the interesting thing. When you convert back to real numbers in Hawking’s model, do you know what you get? You get standard model space-time – the singularity reappears. It is there all the time. It is just concealed behind the artifice of imaginary time. So, as Hawking says, only if we refuse to convert to the real time in which we live are there no singularities. When we go back to the real time in which we live, Hawking says, there would still be singularities.
What these quantum gravity models allow us to do is describe a universe with an absolute beginning in such a way that the singularity doesn’t appear in the description. It is just a different mathematical way of describing the same universe in such a way that in the re-description you don’t have the singular point. But physically speaking, they are the same thing.
Dr. Craig: That is kind of hard to say because theorists often float models as kind of just proposals – theories – and say let’s give this a run for our money. But it is hard to know what they really believe themselves. I am reluctant to answer that question. He does say in his book that today almost everyone believes that the universe and time itself had a beginning at the Big Bang. Whether or not he includes himself in that group I am hesitant to say. But in any case this is the theory that he has championed and has defended. What I am suggesting is that the theory, far from avoiding the beginning of the universe, is actually quite sympathetic to it.
Let me just mention one last theory. Here we come to the extreme edge of cosmological speculation. Ekpyrotic scenarios. These are based upon a different theory of elementary particles than ordinary standard quantum theory. This is based upon something called string theory. On string theory the building blocks of matter are not tiny particles but they are tiny vibrating strings of energy. These strings by vibrating in different ways give rise to the material particles that we see. The fundamental building blocks of matter are these tiny one-dimensional strings. String theory is so complicated and so poorly understood that all of its equations have not even been stated yet much less solved. But that hasn’t deterred some cosmologists from speculating about trying to use string theory to develop models of the universe that would avoid the prediction of the beginning in the standard model. These Ekpyrotic scenarios championed by people like Paul Steinhardt of Princeton University would be an example.
What do these scenarios say? In one sense it is wrong to even call them a model or a theory because they are so undeveloped. They are more like just scenarios. What this scenario suggests is that our universe is one of two three-dimensional membranes (or branes, for short) which are parallel to each other in a higher five-dimensional space. These two membranes are in an eternal cycle of approach and then collapse, spanking together and then retreating and then coming back again. With each collision it causes this universe (which is ours) to expand. The expansion of our universe is renewed each time. This three-dimensional setup exists, as I say, in a higher five-dimensional space.
Not only is this scenario very, very conjectural and incomplete, but it is attended with all sorts of problems. In fact, the Ekpyrotic scenarios really are just the oscillating model writ large in five-dimensions. It is really the same thing as the old oscillating model except put in a five-dimensional scenario. It faces the same problem as did the original. Namely, each time these collide that is equivalent to the universe collapsing back to a singularity. And there is no known physics that would allow the universe to rebound from that or to pass through a singularity to form a new universe. There are all sorts of other problems about this that I could mention, but I will skip over.
I think there is a more fundamental difficulty that has shown that they cannot be extended to the infinite past to avoid the beginning of the universe. Namely, remember I referred to that theorem that was developed by Borde and Vilenkin and then in 2001 strengthened in cooperation with Alan Guth. When Borde and Vilenkin did this with Guth in 2001, what they were able to demonstrate was that their theorem applied not only to inflationary models like Andrei Linde’s it also applied to higher dimensional theories like Steinhardt’s, particularly string cosmology and brane cosmology. It turns out that these scenarios as well cannot be extended into the infinite past. There has to be an initial boundary point at which the universe began to exist. Steinhardt on his website now admits this and recognizes this implication of the Bord-Vilenkin-Guth scenario.
What all this goes to show, I think, is that, as I said two weeks ago, the history of 20th century cosmology in a sense has been the failure of one attempt after another to deny the absolute beginning of the universe predicted on the basis of the standard model. Even scenarios like this Ekpyrotic scenario, which are so speculative and so far removed from experiment that you would think it would be impossible to prove or disprove them, have in fact been falsified insofar as one tries to extend them into the infinite past. I think what we can say minimally is that there is no other theory that is as mathematically consistent, as empirically confirmed by the evidence, or as consonant with our observation, or as confirmed by repeated failures at attempts at its falsification, as the standard Big Bang model. Therefore the person who believes in the creation of the universe out of nothing and an absolute beginning of the universe stands squarely within the scientific mainstream today. It is those who would deny this conclusion that find themselves hard-pressed to show how that is possible.
Next time we will look at a second scientific confirmation of the beginning of the universe which is independent of this one and based upon the thermodynamic properties of the universe.
 Total Running Time: 45:47 (Copyright © 2008 William Lane Craig)