The blogosphere is abuzz with reports about a physics paper, Evidence against fine-tuning for life, written by an evangelical Christian physicist named Don Page, professor of physics at the University of Alberta. The paper is surprisingly non-technical and very easy to read. Also worth reading is Dr. Don Page’s non-technical online presentation, Does God so love the multiverse? Professor Page has since rewritten this presentation as a 26-page scientific article, available here.
The gist of Professor Page’s latest paper is that in an optimally designed fine-tuned universe, we’d expect the fraction of baryons (particles composed of three quarks, such as protons and neutrons) that form organized structures (such as galaxies and eventually living things), to be maximized. However, the facts do not bear this out. In our universe, the observed value of the cosmological constant, lambda-0, is very slightly positive – about 3.5 x 10^(-122) – whereas in an optimally designed universe, the cosmological constant (lambda) should be very slightly negative – somewhere between zero and minus 3.5 x 10^(-122):
[H]ere we are examining the .. view, that a biophilic principle fine tunes lambda to the value that maximizes the fraction of baryons that develop into life. Martel, Shapiro, and Weinberg [11] found that not only does this fraction drop steeply with lambda if it is much larger than lambda-0, but also that it is a decreasing function of lambda for all positive values. The reason is that a positive cosmological constant gives a repulsion between separate particles that reduces the ordinary gravitational attraction and leads to less gravitational condensation of matter. Therefore, other factors being equal, any positive cosmological constant decreases the fraction of baryons that condense to form galaxies and other structures that eventually form living substructures.
As an immediate consequence, no positive value of the cosmological constant (such as the observed value lambda-0) can maximize the fraction of baryons in life. Therefore, the observed positive value of the cosmological constant is evidence against this specific hypothesis of fine tuning for life by a biophilic principle that would
maximize the fraction of baryons that form living organisms or observers.
Later on in his paper, Page admits that his initial assumption, that in a fine-tuned universe the fraction of baryons that form living beings should be maximized, may be mistaken; it may simply be the total number of baryons that form living beings which should be maximized. But then he says that we don’t know how the total number of baryons would depend on lambda (the cosmological constant), and he adds that in their calculations, Martel, Shapiro, and Weinberg just considered the fraction of baryons condensing into structures, as that was something they could calculate. He adds that he’s a little worried about this, especially as the simplest estimates for the total number of baryons tend to be infinite! Not being a scientist, I can’t comment on the simplifying assumption made by Martel, Shapiro, and Weinberg.
In his online presentation, Does God so love the multiverse? , Professor Page speculates that God may have created a multiverse instead of just one universe, because it was simpler for Him to do that, and more elegant as well. A multiverse would still require laws of Nature, and God could well have chosen these laws. Page also adduces some Bayesian arguments in support of the multiverse as well, but I’ll skip over these, as I don’t think they’re very rigorous. Page concludes:
* Multiverses are serious ideas of present science, though not yet proved.
* They can potentially explain fine-tuned constants of physics but are not an automatic panacea for solving all problems.
* Though multiverses should not be accepted uncritically, I would argue that Christians have no more reason to oppose them than they had to oppose Darwinian evolution when it was first proposed. (Emphasis mine – VJT.)
* God might indeed so love the multiverse.
Interestingly, in his technical paper on the multiverse, Professor Page reveals his profound theological bias against the fine-tuning argument:
I personally think it might be a theological mistake to look for fine tuning as a sign of the existence of God. I am reminded of the exchange between Jesus and the religious authorities recorded in the Gospel of Matthew 12:38-41: “Then some of the scribes and Pharisees answered, saying, ‘Teacher, we want to see a sign from You.’ But He answered and said to them, ‘An evil and adulterous generation seeks after a sign, and no sign will be given to it except the sign of the prophet Jonah. For as Jonah was three days and three nights in the belly of the great fish, so will the Son of Man be three days and three nights in the heart of the earth. The men of Nineveh will rise up in the judgment with this generation and condemn it, because they repented at the preaching of Jonah; and indeed a greater than Jonah is here.’” In other words, I regard the death and resurrection of Jesus as the sign given to us that He is indeed the Son of God and Savior He claimed to be, rather than needing signs from fine tuning. (Emphasis mine – VJT.)
Here are a few of my thoughts on Professor Page’s arguments regarding fine-tuning and the multiverse:
Scientific comments
(1) Professor Page’s latest paper undercuts the view that the universe is optimal, but it doesn’t undercut fine-tuning. The evidence for fine-tuning remains compelling. That’s the most important thing that readers need to take away from this whole story.
Some people, upon reading about Page’s paper, may feel massively demoralized, and think: “So the universe wasn’t designed after all.” But this would be a really stupid reaction. Why?
To put the whole matter in perspective, it should be pointed out that the argument really hinges on whether God should have designed a universe with a very, very, tiny negative value for the cosmological constant, or a very, very, tiny positive value. Think of the values we’re talking about here: 3 x 10^(-122) is 3 divided by 1 followed by 122 zeroes. That’s a very small fraction. It’s perfectly legitimate to ask why the universe has such a low value for the cosmological constant. Why isn’t it 3, or 300, or 3 trillion, or 3 with 122 zeroes after it (3 x 10^122)? The riposte, “Because we wouldn’t be here if it wasn’t” is a cop-out, as it merely addresses the question of why we observe a life-compatible value for the cosmological constant (lambda) in our universe. What it fails to address is the question of why a life-friendly universe such as ours exists in the first place.
(2) Fine-tuning would still exist in Nature, even if there were a multiverse, as Professor Page believes. Professor Page’s latest findings fail to dent Dr. Robin Collins’ brilliant defense of the fine-tuning argument in his article, The Teleological Argument: An Exploration of the Fine-Tuning of the Universe (in The Blackwell Companion to Natural Theology, edited by William Lane Craig and J. P. Moreland, 2009, Blackwell Publishing Ltd, ISBN: 978-1-405-17657-6). In his article, Dr. Collins carefully evaluates the version of fine-tuning considered to be most likely by Professor Page – namely, one that combines inflationary cosmology with M-theory. Collins argues that “the laws of the multiverse generator must be just right – fine-tuned – in order to produce life-sustaining universes,” and concludes:
In sum, even if an inflationary/superstring multiverse generator exists, it must have just the right combination of laws and fields for the production of life-permitting universes: if one of the components were missing or different, such as Einstein’s equation or the Pauli-exclusion principle, it is unlikely that any life-permitting universes could be produced. Consequently, at most this highly speculative scenario would explain the fine-tuning of the constants of physics, but at the cost of postulating additional fine-tuning of the laws of nature. (Italics mine – VJT.)
(3) If a multiverse does exist (as it may well do), then Intelligent Design proponents should assume that there must be a good reason for it to exist, and that this reason has to do with the needs of intelligent life. Interestingly, Oxford physicist David Deutsch has provided a possible reason why human beings might need a multiverse: according to him, quantum computers couldn’t perform their computations unless there were other universes. In his article David Deutsch’s many worlds (in Frontiers magazine, December 1998), Deutsch rhetorically asks: “So I issue this challenge to those who still cling to a single-universe world view: if the universe we see around us is all there is, where are the quantum computations performed? I have yet to receive a plausible reply.”
If Deutsch’s argument regarding quantum computers is indeed correct, then the next question we need to ask is: how many universes do humans need, to perform all their quantum computations? And can we use this result to weed out physical theories which postulate an absurdly large or even infinite number of multiverses?
(4) Professor Page admits in his latest paper that if the cosmological constant is less than zero, as he thinks it should be, “the entire universe will recollapse, putting a limit on how much time there is for life to develop, and therefore on what fraction of baryons actually form life” (emphasis mine – VJT). To give the universe enough time for life to evolve, Page argues that the optimal negative value for the cosmological constant needs to be very, very small. On the contrary, I would suggest that maybe the reason why the cosmological constant is positive is that God doesn’t want this universe to one day recollapse. Maybe He wants it to exist forever. Page also admits that the very, very small positive value for the cosmological constant which obtains in our universe has very little (if any) adverse impact on the development of life, after galaxies begin to form in the cosmos: “For a positive cosmological constant no larger than its observed value, once gravitationally bound structures like galaxies develop, lambda appears to have an insignificant effect on the development of life…” So all the fuss in the media over the sub-optimal value of the cosmological constant (lambda) is a bit of a storm in a tea-cup.
(5) Professor Page thinks a multiverse might be more elegant than a single universe. Maybe he’s right. Well, “elegance” is a very nice term, but it’s not much good, scientifically speaking, if you can’t compare it, measure it or quantify it. Is an infinite multiverse more elegant than a finite one, for instance? And if a finite one is more elegant, what’s the most elegant kind of finite multiverse? Unfortunately, in his technical paper, Professor Page doesn’t provide a scientific measure of elegance. Intelligent Design proponents need to press him on this one.
Professor Page also mentions simplicity, but admits in his technical paper that the notion faces a problem, highlighted by Oxford physicist David Deutsch: “simplicity depends on one’s background knowledge that itself depends on the laws of physics.” So we are back at square one.
Theological comments
(6) Professor Page doesn’t like the fine-tuning argument for theological reasons: he thinks humans have no right to ask God to give us a sign of His existence, in the cosmos. For my part, I’m extremely distrustful of a priori theological arguments which take as their premise the assertion that God doesn’t want to reveal Himself too obviously. I’d like to ask: why not? If He made the universe, then presumably He would want to reveal His existence to the intelligent beings that live in it. Professor Page thinks it’s presumptuous to look for a sign of God’s existence in the fine-tuning of the cosmos, because he thinks God wouldn’t want to show Himself like that. For my part, I consider Page’s attitude to be both elitist and exclusive. It’s elitist, because it ignores the mass of ordinary people, struggling with their daily lives, who find it very hard to continue believing in God in a world filled with evil, and who have a deep-felt need for a sign from the heavens which shows that they are indeed part of a Divine plan. Fine-tuning is such a sign. For many people, it provides strong confirmation of their belief that God meant them to be here – confirmation which sustains them in a world filled with trials and assaults on faith.
Professor Page’s response is also theologically exclusive, because the Resurrection is a sign which non-Christians can draw no comfort from. What Page is saying is that if you were not born a Christian, and you live in a land in which the Christian faith is not being widely preached, and you are sincerely trying to find meaning in your life, then God will offer you no evidence of His existence. If you haven’t heard of the Resurrection, then the world will look godless to you. I find that assertion appalling. But in any case, Scripture itself contradicts Page’s position. St. Paul tells us that God’s existence can be clearly known, from the things that He has made (Romans 1: 20). And on a popular level, design arguments for the existence of God have always been the most appealing. We would therefore expect to see the hand of God in Nature. The fine-tuning argument and the argument from the specified complexity we see in living things are the two design arguments which make the best case for God’s existence, at the present time. It would therefre be prudent to follow these leads, and see where they take us.
(7) From a purely religious perspective, I wouldn’t expect this universe to be optimal, anyway. I would expect it to be pretty close to optimal, however. In an optimally designed universe, living things would never die. Religious believers have a name for this optimally designed universe: it’s called Heaven. It’s out there, but we can’t reach it, as it lies beyond our space and time. The constants of Nature must be somewhat different in Heaven, since in our universe they permit only mortal life-forms to arise.
(8) Reading Professor Page’s paper, I was reminded of the atheist philosopher Bradley Monton’s blog post on how he would explain the problem of evil, if he were a believer – The many-universe solution to the problem of evil:
… I’ll present it with a parable. Suppose that God exists, and God is omnipotent and omniscient, and has the desire to be omnibenevolent. So God creates a very nice universe, a universe with no evil. We might at first think that God has fulfilled the criterion of omnibenevolence, but then we recognize that God could do more – God could create another universe that’s also very nice. Agents could exist in that universe that didn’t exist in the first universe, and so there’s an intuitive sense (which is admittedly tricky to make precise mathematically) in which there would be more goodness to reality than there would be were God just to create one universe.
But of course there’s no reason to stop at two – God should create an infinite number of universes. Now, he could just create an infinite number of universes, where in each universe no evil things happen. But in doing so, there would be certain creatures that wouldn’t exist – creatures like us, who exist in a universe with evil, and are essential products of that universe. So God has to decide whether to create our universe as well. What criterion should he use in making this decision? My thought is that he should create all the universes that have more good than evil, and not create the universes that have more evil than good.
So that’s why an omnipotent omniscient omnibenevolent God would create our universe, even though it has evil — our universe adds (in an intuitive sense, setting aside mathematical technicalities) to the sum total of goodness in the universe, and hence it’s worth creating.
I’d like to know what readers think of Professor Monton’s solution to the problem of evil.
(9) I found Page’s comment on Darwinism to be risible. Professor Page writes: “Though multiverses should not be accepted uncritically, I would argue that Christians have no more reason to oppose them than they had to oppose Darwinian evolution when it was first proposed.” On the contrary, Professor: Darwinism, more than anything else in the past 200 years, has shattered religious faith in the Western world.
Concluding remarks
To sum up: Professor Page’s paper suggests that the cosmological constant isn’t optimal: instead of being very, very slightly negative, it’s very, very slightly positive. That may be so, but the remarkable thing is that the cosmological constant is still compatible with life at all.
The existence of the multiverse postulated by Professor Page does not do away with the need for design: indeed, it requires additional fine-tuning of the laws of nature.
The argument from fine-tuning stands.