The Fine-Tuning of the Universe - extract from 'God's Undertaker: has science buried God?' by John Lennox
This article about cosmic fine tuning is an extract from 'God's undertaker: has science buried God?' by John Lennox (Lion Hudson, 2009), pp. 69-76, used with kind permission of the publishers.
Copernicus was responsible for a revolution in scientific thinking. By overturning the idea that the earth was fixed at the centre of the universe, he began a process of demoting the earth’s significance that has resulted in the widespread view that the earth is a fairly typical planet orbiting a fairly typical sun which is positioned in one of the spiral arms of a fairly typical galaxy which, the multiverse theorists will add, is in a fairly typical universe. This cutting of earth down to size is sometimes known as the Copernican Principle.
However, several avenues of research and thought combine to call this principle into serious question. For, the remarkable picture that is gradually emerging from modern physics and cosmology is one of a universe whose fundamental forces are amazingly, intricately, and delicately balanced or ‘fine-tuned’ in order for the universe to be able to sustain life. Recent research has shown that many of the fundamental constants of nature, from the energy levels in the carbon atom to the rate at which the universe is expanding, have just the right values for life to exist, Change any one of them just a little, and the universe would become hostile to life and incapable of supporting it. The constants are precision-tuned, and it is this fine-tuning that many scientists (and others) think demands an explanation. Of course, by the very nature of things, we can only refer to the current state of affairs in the awareness that there are, as always, disagreements among scientists as to the validity of some of the assumptions that underlie fine-tuning calculations and that some views may well change – scientists do not claim to deliver final truth. Nevertheless, fine-tuning has established itself as an aspect of the universe that merits very serious consideration. Let us look, then, at some examples.
For life to exist on earth an abundant supply of carbon is needed. Carbon is formed either by combining three helium nuclei, or by combining nuclei of helium and beryllium. Eminent mathematician and astronomer, Sir Fred Hoyle, found that for this to happen, the nuclear ground state energy levels have to be fine-tuned with respect to each other. This phenomenon is called ‘resonance.’ If the variation were more than 1 percent either way, the universe could not sustain life. Hoyle later confessed that nothing had shaken his atheism as much as this discovery. Even this degree of fine-tuning was enough to persuade him that it looked as if ‘a superintellect has monkeyed with physics as well as with chemistry and biology,’ and that ‘there are no blind forces in nature worth talking about.’[1]
However, in terms of the tolerance permitted, this example pales into insignificance when we consider the fineness of the tuning of some of the other parameters in nature. Theoretical physicist Paul Davies tells us that, if the ratio of the nuclear strong force to the electromagnetic force had been different by 1 part in 1016, no stars could have formed. Again, the ratio of the electromagnetic force-constant to the gravitational force-constant must be equally delicately balanced. Increase it by only one part in 1040 and only small stars can exist; decrease it by the same amount and there will only be large stars. You must have both large and small stars in the universe: the large ones produce elements in their thermonuclear furnaces; and it is only the small ones that burn long enough to sustain a planet with life.
To use Davies’ illustration, that is the kind of accuracy a marksman would need to hit a coin at the far side of the observable universe, twenty billion light years away.[2] If we find that difficult to imagine, a further illustration suggested by astrophysicist Hugh Ross may help.[3] Cover America with coins in a column reaching to the moon (380,000 km or 236,000 miles away), then do the same for a billion other continents of the same size. Paint one coin red and put it somewhere in one of the billion piles. Blindfold a friend and ask her to pick it out. The odds are about 1 in 1040 that she will.
Although we are now in realms of precision far beyond anything achievable by instrumentation designed by humans, the cosmos still has more stunning surprises in store. It is argued that an alteration in the ratio of the expansion and contraction forces by as little as 1 part in 1055 at the Planck time (just 10-43 seconds after the origin of the universe), would have led either to too rapid expansion of the universe with no galaxies forming or to too slow an expansion with consequent rapid collapse.[4]
Yet even this example of precision-tuning is completely eclipsed by what is perhaps the most mind-boggling example of all. Our universe is a universe in which entropy (a measure of disorder) is increasing; a fact which is enshrined in the Second Law of Thermodynamics. Eminent mathematician Sir Roger Penrose writes: ‘Try to imagine the phase space... of the entire universe. Each point in this phase space represents a different possible way that the universe might have started off. We are to picture the Creator, armed with a ‘pin’ – which is to be placed at some point in the phase space… Each different positioning of the pin provides a different universe. Now the accuracy that is needed for the Creator’s aim depends on the entropy of the universe that is thereby created. It would be relatively ‘easy’ to produce a high entropy universe, since then there would be a large volume of the phase space available for the pin to hit. But in order to start off the universe in a state of low entropy – so that there will indeed be a second law of thermodynamics – the Creator must aim for a much tinier volume of the phase space. How tiny would this region be, in order that a universe closely resembling the one in which we actually live would be the result?’
His calculations lead him to the remarkable conclusion that the ‘Creator’s aim’ must have been accurate to 1 part in 10 to the power 10123, that is 1 followed by 10123 zeros, a ‘number which it would be impossible to write out in the usual decimal way, because even if you were able to put a zero on every particle in the universe there would not even be enough particles to do the job.’[5]
Faced with not one, but many such spectacular examples of fine-tuning, it is perhaps not surprising that Paul Davies says, ‘It seems as though someone has fine tuned nature’s numbers to make the universe… The impression of design is overwhelming.’[6]
Up to this point we have mainly been considering fine-tuning at the large-scale cosmological level. When we think of the specific conditions that are needed nearer home in our solar system and on earth, we find that there are a host of other parameters that must be just right in order for life to be possible. Some of them are obvious to us all. The distance from the earth to the sun must be just right. Too near and water would evaporate, too far and the earth would be too cold for life. A change of only 2 per cent or so and all life would cease. Surface gravity and temperature are also critical to within a few per cent for the earth to have a life-sustaining atmosphere – retaining the right mix of gases necessary for life. The planet must rotate at the right speed: too slow and temperature differences between day and night would be too extreme, too fast and wind speeds would be disastrous. And so the list goes on. Astrophysicist Hugh Ross[7] lists many such parameters that have to be fine-tuned for life to be possible, and makes a rough but conservative calculation that the chance of one such planet existing in the universe is about 1 in 1030.
An intriguing angle on this theme has been opened up in the recent book The Privileged Planet, by Guillermo Gonzalez and Jay W. Richards.[8] The authors draw attention to the earth’s remarkable suitability as a place on which to do science. Their thesis is that, of all possible places in the universe, earth enjoys conditions that not only allow for habitability but simultaneously are extremely congenial to the making of ‘a stunning diversity of measurements, from cosmology and galactic astronomy to stellar astrophysics and geophysics.’[9] Once one begins to think about it, examples are abundant, some of them very obvious. We might easily have found ourselves in a part of the universe where we could not see into deep space because of too much starlight; our atmosphere might have been opaque or simply translucent rather than transparent. Others are less obvious: witness the fact that the sizes of the moon and the sun and their distances from the earth are just right that a perfect eclipse is possible. This occurs when the black disc of the moon just barely covers the glowing disc of the sun so that the tin ring of the chromosphere (the ‘atmosphere’) of the sun is visible and can therefore be investigated scientifically – as a result of which we not only know a great deal more about the sun than we otherwise would, but we were also able to get initial confirmation of the bending of light by gravity predicted by Einstein’s theory of general relativity.
Their conclusion is this: ‘And yet as we stand gazing at the heavens beyond our little oasis, we gaze not into a meaningless abyss but into a wondrous arena commensurate with our capacity for discovery. Perhaps we have been staring past a cosmic signal far more significant than any mere sequence of numbers, a signal revealing a universe so skilfully crafted for life and discovery that it seems to whisper of an extra-terrestrial intelligence immeasurably more vast, more ancient, and more magnificent than anything we’ve been willing to expect or imagine.’[10]
Arno Penzias, who used the propitious position of the space-platform of earth to make the brilliant discovery of the ‘echo of the beginning,’ the cosmic background microwave radiation, sums up the position as he sees it: ‘Astronomy leads us to a unique event, a universe which was created out of nothing, one with the very delicate balance needed to provide exactly the right conditions required to permit life, and one which has an underlying (one might say ‘supernatural’) plan.’[11]
We should note that the preceding arguments are not ‘God of the gaps’ arguments; it is advance in science, not ignorance of science, that has revealed this fine-tuning to us. In that sense there is no ‘gap’ in the science. The question is rather: How should we interpret the science? In what direction is it pointing?
The anthropic principle
This perception on the part of scientists, that the universe has to be very precisely structured in order to support life, has been called the anthropic principle (Greek: anthropos = man). In its weak form (the weak anthropic principle), it runs like this: ‘the observable universe has a structure which permits the existence of observers.’ Clearly, the precise status of such a statement is open to debate: Is it a tautology? Is it a principle, in the sense that it helps provide explanations etc.? Whatever the answer, at the very least its formulation draws attention to the fact that viable theories of the cosmos must take into account the existence of observers.
Some scientists and philosophers[12] maintain that we ought not to be surprised at the order and fine-tuning we see in the universe around us, since if it did not exist then carbon-based life would be impossible, and we would not be here to observe the fine-tuning. In other words they use the anthropic principle against the inference of design. In fact, Richard Dawkins in The God Delusion tells us that the anthropic principle and God function as alternative explanations.[13] But this is false logic in two ways. Dawkins is not only presenting us with false alternatives, but the former of these does not belong to the category of explanation at all. All the anthropic principle does is to tell us that for life to exist, certain necessary conditions must be fulfilled. But what it does not tell us is why those necessary conditions are fulfilled, nor how, granted they are fulfilled, life arose. Dawkins is making the elementary mistake of thinking that necessary conditions are sufficient. But they are not: in order to get a first class degree at Oxford it is necessary to get into the University; but, as many students know, it is certainly not sufficient. The anthropic principle, far from giving an explanation of the origin of life, is an observation that gives rise to the need for such an explanation.
Philosopher John Leslie sees this point. He says[14] that using the anthropic principle against design ‘sounds like arguing that if you faced a firing squad with fifty guns trained on you, you should not be surprised to find that you were alive after they had fired. After all, that is the only outcome you could possibly have observed – if one bullet had hit you, you would be dead. However, you might still feel that there is something which very much needs explanation: namely why did they all miss? Was it by deliberate design? For there is no inconsistency in not being surprised that you do not observe that you are dead, and being surprised to observe that you are still alive.’[15]
Leslie argues that the fine-tuning argument presents us with a choice between, at most, two possibilities. The first of these is that God is real. The only way to avoid this conclusion, according to Leslie, is to believe in the so-called ‘many worlds’ or ‘multiverse’ hypothesis, (popularized in David Deutsch’s book The Fabric of Reality[16]) which postulates the simultaneous existence of many, possibly infinitely many, parallel universes in which (almost) anything which is theoretically possible will ultimately be actualized, so that there is nothing surprising in the existence of a universe like ours. This is the view opted for by astronomer Sir Martin Rees, who in his book Just Six Numbers[17] discusses the six fine-tuned numbers that he holds to be most significant as controllers of the characteristics of the universe.
Deutsch bases his theory on the interpretation of quantum mechanics due to Hugh Everett III in which the basic idea is that at each act of quantum measurement the universe splits into a series of parallel universes, in which all of the possible outcomes occur. Although the Everett interpretation holds out certain advantages over other theories – for example, by obviating the necessity of faster than light signalling – many scientists feel that an explanation which involves undetectable universes and represents in addition an extreme violation of the Occam’s Razor principle of searching for theories that do not involve unnecessary multiplication of hypotheses, goes well beyond science into metaphysics. There is much speculation and very little evidence.
John Polkinghorne, for instance, himself an eminent quantum theorist, rejects the many-universe interpretation: ‘Let us recognize these speculations for what they are. They are not physics, but in the strictest sense, metaphysics. There is no purely scientific reason to believe in an ensemble of universes. By construction these other worlds are unknowable by us. A possible explanation of equal intellectual respectability – and to my mind greater economy and elegance – would be that this one world is the way it is, because it is the creation of the will of a Creator who purposes that it should be so.’[18] Philosopher Richard Swinburne goes even further. ‘To postulate a trillion-trillion other universes, rather than one God, in order to explain the orderliness of our universe, seems the height of irrationality.’[19]
Cosmologist Edward Harrison reacts in a very similar way. ‘Here is the cosmological proof of the existence of God – the design argument of Paley – updated and refurbished. The fine-tuning of the universe provides prima facie evidence of deistic design. Take your choice: blind chance that requires multitudes of universes, or design that requires only one… Many scientists, when they admit their views, incline towards the teleological or design argument.’[20] Arno Penzias puts the argument the other way round: ‘Some people are uncomfortable with the purposefully created world. To come up with things that contradict purpose, they tend to speculate about things they haven’t seen.’[21]
It should, however, be pointed out that, although Leslie may be correct in suggesting that fine-tuning means either that there is a God or a multiverse, logically these two options are not mutually exclusive, although they are usually presented as such. After all, parallel universes could be the work of a Creator. Furthermore, as philosopher of physics Michael Lockwood has observed, Leslie’s firing squad argument for this universe is not actually negated by postulating a multiverse. The element of surprise and need for explanation exists within whichever universe in which the fine-tuning is being observed. After all, the probability that a given person obtains a run of ten sixes in throwing a dice is not altered by the fact that there may be many people throwing dice in the same city at the same time.
In a similar vein Christian de Duve writes: ‘Even if the theory turns out to be correct, the deduction drawn from it by Rees and Weinberg strikes me as what is called in French ‘drowning the fish.’ Whether you use all the water in the oceans to drown the animal, it will still be there affirming its presence. However many universes one postulates, ours can never be rendered insignificant by the magnitude of this number... what appears to me as supremely significant is that a combination capable of giving rise to life and mind should exist at all.’[22] Therefore the multiverse argument does not in fact weaken the design arguments advanced above.
It is interesting that Martin Rees concedes that the fine-tuning of the universe is compatible with theism but says he prefers the multiverse theory: ‘If one does not believe in providential design, but still thinks the fine-tuning needs some explanation, there is another perspective – a highly speculative one, so I should reiterate my health warning at this stage. It is the one I much prefer, however, even though in our present state of knowledge any such preference can be no more than a hunch.’[23] Now preference is a personal thing to which each one of us is of course entitled, but it takes us beyond the boundaries of what most of us would think of as science.
Another version of the multiverse theory, the many worlds interpretation of quantum mechanics, is that every logically possible universe exists. However, if every possible universe exists, then, according to philosopher Alvin Plantinga of Notre Dame University, there must be a universe in which God exists – since his existence is logically possible – even though highly improbable in the view of the New Atheists. It then follows that, since God is omnipotent, he must exist in every universe and hence there is only one universe, this universe, of which he is the Creator and Upholder.
The concept of many worlds is clearly fraught with logical, and not only scientific, difficulties.[24] It can also present moral difficulties. If every logically possible universe exists, then presumably there is one in which I exist (or a copy of me?) and in which I am a murder – or worse. The concept seems therefore also to lead to moral absurdity.
Finally, Arno Penzias reminds us that the notion that there is a teleological dimension in the universe goes back millennia. He writes: ‘The best data we have (concerning the Big Bang) are exactly what I would have predicted, had I nothing to go on but the five books of Moses, the Psalms, and the Bible as a whole.’[25]
We notice in passing Penzias’ use of the word ‘predicted.’ Here is another major counter-example to the commonly held notion that there is no element of predictability (and thus no scientific dimension) in the theistic account of creation. For Penzias, as for many other scientists, the majestic words with which Genesis begins have lost none of their relevance or power: ‘In the beginning God created the heavens and the earth.’ It is perhaps not surprising, therefore, that the idea of the Big Bang was first mooted (in Nature in 1931) by a physicist and astronomer, Georges Lemaitre, who was also a priest.[26]
So much then for the views of physicists and cosmologists. We must presently turn to the biologists. But before doing so we need to emphasize the fact that the arguments we have used from cosmology and physics are arguments based on standard contemporary science that enjoys widespread acceptance. They are not arguments that involve challenging any of the mainstream claims of science, and, as we have pointed out above, they are certainly not ‘God of the gaps’ arguments: they do not reduce to ‘Science can’t explain it, therefore God did it.’ It is for these two reasons that fine-tuning arguments, for example, gain a ready hearing from most scientists, even though they may agree or disagree with the conclusions we have drawn from them. Such arguments have the ring of being compatible with authentic scientific activity.
Extract from God’s Undertaker: has science buried God? by John C. Lennox (Lion Hudson, 2009), pp. 69-76, used with kind permission of the publishers.
[1] Annual Reviews of Astronomy and Astrophysics, 20, 1982, p.16.
[2] God and the New Physics, London, J M Dent and Sons, 1983.
[3] The Creator and the Cosmos, Colorado Springs, Navpress, 1995 p. 117.
[4] See A H Guth ‘Inflationary Universe,’ Physical Review, D, 23, 1981, p. 348.
[5] The Emperor’s New Mind, Oxford, Oxford University Press, 1989, p. 344
[6] The Cosmic Blueprint, New York, Simon & Schuster, 1988, p. 203.
[7] op. cit. pp. 138-139
[8] Washington DC, Regnery, 2004.
[9] op. cit. p. xiii
[10] op. cit. p. 335
[11] Cosmos, Bios and Theos, Margenau and Varghese eds, La Salle, IL, Open Court, 1992, p. 83
[12] For example, Barrow and Tipler, The Anthropic Cosmological Principle, Oxford, University Press, 1988, p. 566
[13] The God Delusion, Bantam Press, 2006, p. 164.
[14] Universes, London, Routledge, 1989, p. 14
[15] See also the discussion in A. McGrath, The Foundations of Dialogue in Science and Religion, Blackwell, Oxford, 1998, p. 114 ff
[16] London, Penguin, 1997
[17] London, Weidenfeld and Nicholson, 1999
[18] One World, London, SPCK, 1986, p. 80
[19] Is There a God? Oxford, Oxford University Press, 1995, p. 68
[20] E. Harrison, Masks of the Universe, New York, Macmillan, 1985 pp. 252, 263
[21] In Denis Brian, Genius Talk, New York, Plenum, 1995
[22] de Duve, Life Evolving, op. cit p. 299
[23] Our Cosmic Habitat, London, Phoenix, 2003, p. 164
[24] For a very comprehensive in-depth survey of this whole field see Rodney Holder, God, the Multiverse and everything, Ashgate Press, 2008
[25] In Malcolm Browne, New York Times, ‘Clues to the Universe’s Origin Expected,’ 12 March 1978, p. 1
[26] Lemaitre called his original idea the ‘hypothesis of the primeval atom.
