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The Scientific Case
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The Scientific Case Against
A God Who Created the UniversePublished on February 13, 2007
Presented here is an argument based on modern physics and cosmology against the existence of a God who created the universe. It can be summarized as follows:
1. Hypothesize a God who is the highly intelligent and powerful supernatural creator of the physical universe.
2. We can reasonably expect that empirical evidence should exist for a purposeful and supernatural creation of this cosmos, such as the observed violation of one or more laws of physics.
3. No empirical evidence for a purposeful creation of the cosmos can be found. No universal laws of physics were violated at the origin of the universe in which we reside.
4. Modern cosmology indicates that the initial state of our universe was one of maximum chaos so that it contains no memory of a creator.
5. Scientists can provide plausible, purely natural scenarios based in well-established cosmological theories that show how our universe may have arisen out of an initial state of nothingness.
6. We can conclude beyond a reasonable doubt that a God who is the highly intelligent and powerful supernatural creator of the physical universe does not exist.
From a modern scientific perspective, what are the empirical and theoretical implications of a supernatural creation? We need to seek evidence that the universe (1) had an origin and (2) that origin cannot have happened naturally. One sign of a supernatural creation would be a direct empirical confirmation that a miracle was necessary in order to bring the universe into existence. That is, cosmological data should either show evidence for one or more violations of well-established laws of nature or the theories that successfully describe those data should require some causal ingredient that cannot be understood in purely material or natural terms.
Now, as philosopher David Hume pointed out centuries ago, many problems exist with the whole notion of miracles. Three types of possible miracles can be identified: (1) violations of established laws of nature, (2) inexplicable events, and (3) highly unlikely coincidences.
If a violation of an established law of nature is observed, then we might more reasonably surmise that the law was wrong rather than conclude that an occurrence of divine intervention has taken place. If we simply define a miracle as an inexplicable occurrence, then how can we be sure that an explanation will not someday be found? If we view some highly unlikely coincidence as a miracle, how can we know it still was not a random accident? These pose serious questions for anyone arguing from miracles to the existence of God.1
However, that is not the task I have undertaken.
Theologian Richard Swinburne, who has undertaken that task, suggests that we define a miracle as a non-repeatable exception to a law of nature.2 Of course, we can always redefine the law to include the exception, but that would be somewhat arbitrary. Laws are meant to describe repeatable events. So, we will seek evidence for violations of well-established laws that do not repeat themselves in any lawful pattern.
No doubt God, if he exists, is capable of repeating miracles if he so desires. However, repeatable events provide more information that may lead to an eventual natural explanation, while an unexplained, unrepeated event is likely to remain unexplained. Let us give the God hypothesis every benefit of the doubt and keep open the possibility of a miraculous origin for inexplicable events and unlikely coincidences, examining any such occurrences on an individual basis. If even with the loosest definition of a miracle none is observed to occur, then we will have obtained strong support for the case against the existence of a God who directs miraculous events.
Let us proceed to look for evidence of a miraculous creation in our observations of the cosmos.
Creating Matter
The universe currently contains a large amount of matter that is characterized by the physical quantity we define as mass. Prior to the twentieth century, it was believed that matter could neither be created nor destroyed, just changed from one type to another. So the very existence of matter seemed to be a miracle, a violation of the assumed law of conservation of mass that occurred just once�at the creation.
However, in his special theory of relativity published in 1905, Albert Einstein showed that matter can be created out of energy and can disappear into energy. His famous formula E = mc2 relates the mass m of a body to an equivalent rest energy, E, where c is a universal constant, the speed of light in a vacuum. That is, for all practical purposes, mass and rest energy are equivalent, with a body at rest still containing energy.
When a body is moving, it carries an additional energy of motion called kinetic energy. In chemical and nuclear interactions, kinetic energy can be converted into rest energy, which is equivalent to generating mass.3 Also, the reverse happens; mass or rest energy can be converted into kinetic energy. In that way, chemical and nuclear interactions can generate kinetic energy, which then can be used to run engines or blow things up.
So, the existence of mass in the universe violates no law of nature. It can come from energy. But, where does the energy come from? One of the most important principles of physics is the law of conservation of energy, also known as the first law of thermodynamics, which requires that energy come from somewhere. In principle, the creation hypothesis could be confirmed by the direct observation or theoretical requirement that conservation of energy was violated 13.7 billion years ago at the start of the big bang.
However, neither observations nor theory indicate this to have been the case. The first law allows energy to convert from one type to another as long as the total for a closed system remains fixed. Remarkably, the sum of the measured sums of the rest and kinetic energies of the bodies in the universe seems to be exactly cancelled by the negative potential energy that results from their mutual gravitational interactions. Within small measurement errors and quantum uncertainties, the mean energy density of the universe is exactly what it should be for a universe that appeared from an initial state of zero energy, within a small quantum uncertainty.
Furthermore, a close balance between positive and negative energy is predicted by the modern version of the big bang theory called the inflationary big bang, according to which the universe underwent a period of rapid, exponential inflation during a tiny fraction of its first second. The inflationary theory has recently undergone a number of stringent observational tests that would have been sufficient to prove it false. So far, it has passed these tests with flying colors.4
In short, the existence of matter in the universe did not require the violation of energy conservation at the assumed creation. In fact, the data strongly support the hypothesis that no such miracle occurred. If we regard such a miracle as predicted by the creator hypothesis, then that prediction is not confirmed.
Creating Order
Another prediction of the creator hypothesis also fails to be confirmed by the data. If the universe were created, then it should have possessed some degree of order at the creation��the design that was inserted at that point by the Grand Designer. This expectation of order is usually expressed in terms of the second law of thermodynamics, which states that the total entropy or disorder of a closed system must remain constant or increase with time. It would seem to follow that if the universe today is a closed system, it could not always have been so. At some point in the past, order must have been imparted from the outside.
Prior to 1929, this was a strong argument for a creation. However, in that year astronomer Edwin Hubble reported that the galaxies are moving away from one another at speeds approximately proportional to their distance, indicating that the universe is expanding. This formed the earliest evidence for the big bang. For example, an expanding universe can have started in total chaos and still form localized order consistent with the second law.
The simplest way to see this is with a (literally) homey example. Suppose that whenever you clean your house, you empty the collected rubbish by tossing it out the window into your yard. Eventually the yard would be filled with rubbish. However, you can continue doing this with a simple expedient. Just keep buying up the land around your house and you will always have more room to toss the rubbish. You are able to maintain localized order��in your house��at the expense of increased disorder in the rest of the universe.
Similarly, parts of the universe can become more orderly as the rubbish, or entropy, produced during the ordering process (think of it as disorder being removed from the system being ordered) is tossed out into the larger, ever-expanding surrounding space. The total entropy of the universe increases as the universe expands, as required by the second law. However, the maximum possible entropy increases even faster leaving increasingly more room for order to form. The reason for this is that the maximum entropy of a sphere of a certain radius (we are thinking of the universe as a sphere) is that of a black hole of that radius. The expanding universe is not a black hole and so has less than maximum entropy. Thus, while becoming more disorderly on the whole as time goes by, our expanding universe is not maximally disordered. But, once it was.
Suppose we extrapolate the expansion back 13.7 billion years to the earliest definable moment when the universe was confined to the smallest possible region of space that can be operationally defined, a Planck sphere that has a radius equal to the Planck length, 1.6 x 10-35 meter. As expected from the second law, the universe at that time had lower entropy than it has now. However, that entropy was also as high as it possibly could have been for an object that small, because a sphere of Planck dimensions is equivalent to a black hole.
This may require further elaboration. We seem to be saying that the entropy of the universe was maximal when the universe began, yet it has been increasing ever since. Indeed, that�s exactly what we are saying. When the universe began, its entropy was the highest it could be for an object of that size, because the universe was equivalent to a black hole from which no information can be extracted. Currently, the entropy is higher, but not maximal, that is, not as high as it could be for an object of the universe�s current size. The universe is no longer a black hole.
When, at the beginning of the big bang, the entropy was maximal, the disorder was complete and no structure was present. So, the universe began with no structure, but has structure today because its entropy is no longer maximal.
In short, according to our best current cosmological understanding, our universe began with no structure or organization, designed or otherwise. It was a state of chaos.
We are thus forced to conclude that the order we now observe could not have been the result of any initial design built into the universe at the so-called creation. The universe preserves no record of what went on before the big bang. The creator, if he existed, left no imprint.
Beginning and Cause
The empirical fact of the big bang has led some theists to argue that this, in itself, demonstrates the existence of a creator. In 1951, Pope Pius XII told the Pontifical Academy, �Creation took place in time, therefore there is a Creator, therefore God exists.�5 The astronomer/priest Georges-Henri Lema�tre, who first proposed the idea of a big bang, wisely advised the Pope not to make this statement �infallible.�
Christian apologist William Lane Craig has made a number of sophisticated arguments that he claims show that the universe must have had a beginning and that beginning implies a personal creator.6 One argument is based on general relativity, the modern theory of gravity that was published by Einstein in 1916 and which has, since then, passed many stringent empirical tests.7
In 1970, cosmologist Stephen Hawking and mathematician Roger Penrose, using a theorem derived earlier by Penrose, proposed that a singularity exists at the beginning of the big bang.8 Extrapolating general relativity back to zero time, the universe gets smaller and smaller while the density of the universe and the gravitational field increases. As the size of the universe goes to zero, the density and gravitational field, at least according to the mathematics of general relativity, become infinite. At that point, Craig claims, time must stop and, therefore, no prior time can exist.
However, Hawking has repudiated his own earlier proof. In his bestseller A Brief History of Time he avers, �There was in fact no singularity at the beginning of the universe.�9 This revised conclusion, concurred to by Penrose, follows from quantum mechanics, the theory of atomic processes that was developed in the years following the introduction of Einstein�s theories of relativity. Quantum mechanics, which also is now confirmed to great precision, tells us that general relativity, at least as currently formulated, must break down at times less than the Planck time, 6.4 x 10-44 second, and distances smaller than the Planck length, mentioned earlier. It follows that general relativity cannot be used to imply that a singularity occurred prior to the Planck time and Craig�s use of the singularity theorem for a beginning of time is invalid.
Craig and other theists also make another, related argument that the universe had to have had a beginning at some point because if it were infinitely old, it would have taken an infinite time to reach the present. However, as philosopher Keith Parsons has pointed out, �To say the universe is infinitely old is to say that it had no beginning�not a beginning that was infinitely long ago.�10
Infinity is an abstract mathematical concept that was precisely formulated in the work of mathematician Georg Cantor in the late nineteenth century. However, the symbol �∞� is used in physics simply as a shorthand for �a very big number.� Physics is counting. In physics, time is simply the count of ticks on a clock. You can count backward as well as forward. Counting forward you can get a very big but never mathematically infinite positive number and time �never ends.� Counting backward you can get a very big but never mathematically infinite negative number and time �never begins.� Just as we never reach positive infinity, we never reach negative infinity. Even if the universe does not have a mathematically infinite number of events in the future, it still need not have an end. Similarly, even if the universe does not have a mathematically infinite number of events in the past, it still need not have a beginning. We can always have one event follow another, and we can always have one event precede another.
Craig claims that if it can be shown that the universe had a beginning, this is sufficient to demonstrate the existence of a personal creator. He casts this in terms of the kal�m cosmological argument, which is drawn from Islamic theology.11 The argument is posed as a syllogism:
1. Whatever begins to exist has a cause.
2. The universe began to exist.
3. Therefore, the universe has a cause.
The kal�m argument has been severely challenged by philosophers on logical grounds,12 which need not be repeated here since we are focusing on the science. In his writings, Craig takes the first premise to be self-evident, with no justification other than common, everyday experience. That�s the type of experience that tells us the world is flat.
In fact, physical events at the atomic and subatomic level are observed to have no evident cause. For example, when an atom in an excited energy level drops to a lower level and emits a photon, a particle of light, we find no cause of that event. Similarly, no cause is evident in the decay of a radioactive nucleus.
Craig has retorted that quantum events are still �caused,� just caused in a non-predetermined manner�what he calls �probabilistic causality.� In effect, Craig is thereby admitting that the �cause� in his first premise could be an accidental one, something spontaneous�something not predetermined. By allowing probabilistic cause, he destroys his own case for a predetermined creation.
We have a highly successful theory of probabilistic causes�quantum mechanics. It does not predict when a given event will occur and, indeed, assumes that individual events are not predetermined. The one exception occurs in the interpretation of quantum mechanics given by David Bohm. 13 This assumes the existence of yet undetected sub-quantum forces. While this interpretation has some supporters, it is not generally accepted because it requires superluminal connections that violate the principles of special relativitiy.14 More important, no evidence for sub-quantum forces has been found.
Instead of predicting individual events, quantum mechanics is used to predict the statistical distribution of outcomes of ensembles of similar events. This it can do with high precision. For example, a quantum calculation will tell you how many nuclei in a large sample will have decayed after a given time. Or you can predict the intensity of light from a group of excited atoms, which is a measure of the total number of photons emitted. But neither quantum mechanics nor any other existing theory�including Bohm�s�can say anything about the behavior of an individual nucleus or atom. The photons emitted in atomic transitions come into existence spontaneously, as do the particles emitted in nuclear radiation. By so appearing, without predetermination, they contradict the first premise.
In the case of radioactivity, the decays are observed to follow an exponential decay �law.� However, this statistical law is exactly what you expect if the probability for decay in a given small time interval is the same for all time intervals of the same duration. In other words, the decay curve itself is evidence for each individual event occurring unpredictably and, by inference, without being predetermined.
Quantum mechanics and classical (Newtonian) mechanics are not as separate and distance from one another as is generally thought. Indeed, quantum mechanics changes smoothly into classical mechanics when the parameters of the system, such as masses, distances, and speeds approach the classical regime.15 When that happens, quantum probabilities collapse to either zero or 100 percent, which then gives us certainty at that level. However, we have many examples where the probabilities are not zero or 100 percent. The quantum probability calculations agree precisely with the observations made on ensembles of similar events.
Note that, even if the kal�m conclusion were sound and that the universe had a cause, why could that cause itself not be natural? As it is, the kal�m argument fails both empirically and theoretically without ever having to bring up the second premise about the universe having a beginning.
Nevertheless, another nail in the coffin of the kal�m argument is provided by the fact that the second premise also fails. As we saw above, the claim that the universe began with the big bang has no basis in current physical and cosmological knowledge. The observations confirming the big bang do not rule out the possibility of a prior universe. Theoretical models have been published suggesting mechanisms by which our current universe appeared from a pre-existing one, for example, by a process called quantum tunneling or so-called �quantum fluctuations.�16 The equations of cosmology that describe the early universe apply equally for the other side of the time axis, so we have no reason to assume that the universe began with the big bang.
We have already seen that no miracle is evident in the big bang. It follows that its appearance could have been natural. Indeed, this is the more rational conclusion based on the absence of any violation of known physical principles. Prominent physicists and cosmologists have published, in reputable scientific journals, a number of proposals for how the universe could have come about �from nothing� naturally.17 These are speculative, to be sure, but they are speculations based on established knowledge. None violate any known laws of physics. These authors do not claim to �prove� that this is how it all happened. The burden of proof is on those who wish to claim these scenarios are impossible.
In short, empirical data and the theories that successfully describe those data indicate that the universe did not come about by a purposeful creation. Based on our best current scientific knowledge, we conclude beyond a reasonable doubt that a God who is the highly intelligent and powerful supernatural creator of the physical universe does not exist.
NOTES
1. For a discussion of these problems, see Nicholas Everitt, The Non-existence of God (London: Routledge, 2004), chapter 6.
2. Richard Swinburne, The Existence of God (Oxford: Clarendon, 1979), p. 229.
3. It is commonly thought that only nuclear reactions convert between rest and kinetic energy. This also happens in chemical reactions. However, the changes in the masses of the reactants in that case are too small to be generally noticed.
4. See, for example, Alan Guth, The Inflationary Universe (New York: Addison-Wesley, 1997).
5. Pius XII, �The Proofs for the Existence of God in the Light of Modern Natural Science,� Address of Pope Pius XII to the Pontifical Academy of Sciences, November 22, 1951, reprinted as �Modern Science and the Existence of God,� The Catholic Mind 49 (1972): 182-92.
6. Theism, Atheism, and Big Bang Cosmology, edited by William Lane Craig and Quentin Smith (Oxford: Clarendon, 1993).
7. See, for example, Clifford M. Will, Was Einstein Right? Putting General Relativity to the Test (New York: Basic, 1986).
8. Stephen Hawking and Roger Penrose, �The Singularities of Gravitational Collapse and Cosmology,� Proceedings of the Royal Society of London, series A, 314 (1970): 529-48.
9. Stephen Hawking, A Brief History of Time: From the Big Bang to Black Holes (New York: Bantam, 1988), p. 50.
10. Keith Parsons in J. P. Moreland and Kai Nielson, Does God Exist? The Debate between Theists & Atheists (Amherst, NY: Prometheus, 1993), p. 187.
11. William Lane Craig, The Kal�m Cosmological Argument (London: Macmillan, 1979) and Reasonable Faith (Wheaton, IL: Crossways, 1994). See also William Lane Craig, The Cosmological Argument from Plato to Leibniz (London: Macmillan, 1980) for a history of cosmological arguments.
12. Quentin Smith in Theism, Atheism, and Big Bang Cosmology; Everitt, The Non-existence of God, pp. 68-72.
13. David Bohm and B. J. Hiley, The Undivided Universe: An Ontological Interpretation of Quantum Mechanics (London: Routledge, 1993).
14. Discussed in detail in Victor J. Stenger, The Unconscious Quantum: Metaphysics in Modern Physics and Cosmology (Amherst, NY: Prometheus, 1995).
15. Quantum mechanics becomes classical mechanics when Planck�s constant h is set equal to zero.
16. David Atkatz and Heinz Paegels, �Origin of the Universe as Quantum Tunneling Event,�
Physical Review D25 (1982): 2065-73; Alexander Vilenkin, �Birth of Inflationary Universes,� Physical Review D27 (1983): 2848-55; David Atkatz, �Quantum Cosmology for Pedestrians,� American Journal of Physics 62 (1994): 619-27.17. Edward P. Tryon, �Is the Universe a Vacuum Fluctuation?� Nature 246 (1973): 396-97; Vilenkin, �Birth of Inflationary Universes�; Andre Linde, �Quantum Creation of the Inflationary Universe,� Lettere Al Nuovo Cimento 39 (1984): 401-5.
Victor J. Stenger is emeritus professor of physics and astronomy at the University of Hawaii and adjunct professor of philosophy at the University of Colorado. He is the author of five published books, with another two in press. This article is excerpted from his forthcoming book, God: The Failed Hypothesis How Science Shows That God Does Not Exist, submitted for publication.
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