Many Changes to the Laws of Physics Would be Life-Prohibiting

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In my previous blog, I discussed how the initial conditions of our universe had to be extremely finely-tuned to support life of any kind anywhere in the universe. As part of my ongoing series on how fine-tuning provides evidence for the existence of God, I now turn to the laws of physics themselves. It turns out that life seems to require all 4 fundamental forces of physics. Let’s do a quick survey of some of the many ways that alternate physics could have been life-prohibiting:

1)      Gravity is essential in the formation of stars and planets. As I discussed in a previous blog, life needs something like stars as a long-lived stable energy source. Also, as cosmologist Luke Barnes has pointed out: “if gravity were repulsive rather than attractive, then matter wouldn’t clump into complex structures. Remember: your density, thank gravity, is 1030 times greater than the average density of the universe.”

2)      The strong nuclear force is necessary to hold together the protons and neutrons in the nucleus. Without this fundamental force, no atoms would exist beyond hydrogen and thus there would be no meaningful chemistry and thus no possibility for intelligent life. The positively charged protons in the nucleus repel each other but thankfully the strong nuclear force is sufficiently stronger than electromagnetic repulsion. If the strong force acted at long ranges like gravity or electromagnetism, then no atoms would exist because it would dominate over the other forces. Barnes notes that “any structures that formed would be uniform, spherical, undifferentiated lumps, of arbitrary size and incapable of complexity.[1]”

3)      The electromagnetic force accounts for chemical bonding and for why electrons orbit the nucleus of atoms. Without chemistry, there is no plausible way to store and replicate information such as would be necessary for life. Light supplied by stars is also of critical importance to life in overcoming the tendency towards disorder, as dictated by the Second Law of Thermodynamics. Barnes points out that without electromagnetism, “all matter would be like dark matter, which can only form large, diffuse, roughly spherical haloes.[2]” Suppose like charges attracted and opposites repelled (in contrast with the behavior in our universe), there would be no atoms.

4)      The weak nuclear force plays a key role during core-collapse supernova[3] in the expulsion of key heavier elements, making them available for life rather than just entombed forever in dying stars. Also, the weak force enables the key proton-proton reaction which powers stars in our universe. There is a clever paper by Harnik[4] that attempts to find a life-permitting universe without the weak force but only at the expense of a “judicious parameter adjustment.” See this discussion of the additional finely-tuned constants that were necessary to compensate for the lack of a weak force.[5] Also, some physicists think that the weak force is necessary for there to be matter in our universe.[6]

A region of star formation in a small nearby dwarf galaxy (N90) as captured by the Hubble telescope:
StarFormation

The existence of matter in our universe relies on some asymmetries in physics that are not yet precisely understood. Most physical reactions produce matter and antimatter in equal proportions and these products would simply annihilate each other upon contact, resulting in a matter-less (and therefore lifeless) universe consisting solely of radiation. We’re fortunate that the laws are such that this asymmetry produces a slight excess of matter over antimatter (about 1 part in ten billion)[7]! It would be premature to try to make a numerical claim that a constant has to be finely-tuned to permit this phenomenon but this unusual asymmetry provides yet another example of how different physics could have been catastrophic for life.

Another key physics principle that is critical for life is quantization. Values are defined as being ‘quantized’ if they can only take on discrete rather than continuous possibilities. Without quantized orbits electrons would be sucked into the nucleus and no chemistry would be possible. This quantization also leads to stable orbitals and consistent chemical properties. If electrons could orbit the nucleus anywhere such as is permissible for planets orbiting a star, then a given chemical element would have properties which are too variable for information storage of the type needed for intelligent life. Consider how the DNA in your genome would become cancerous within a day if its properties/information content were constantly varying. Also, consider how a breath of oxygen could conceivably become poisonous if its properties had no consistency.

Some other aspects of quantum mechanics are also very important to life. We need the Pauli Exclusion Principle so that all electrons don’t just reside in the lowest energy-level orbital. The multiple levels of orbitals contribute greatly to the richness and diversity of chemistry. Not all types of particles follow the Pauli Exclusion Principle – if electrons were bosons rather than fermions they wouldn’t be restricted by this principle. The Pauli Exclusion Principle coupled with the quantization of electron orbitals is responsible for giving matter its rigidity, which is important for the existence of stable structures. Moreover, without quantum mechanics, atoms would decay in about 10-13 seconds as Earnshaw’s theorem demonstrates based on classical mechanics.

Physicist Leonard Susskind points out yet another way that physics could have been life-prohibiting:

‘The photon is very exceptional. It is the only elementary particle, other than the graviton, that has no mass… Were the photon mass even a tiny fraction of the electron mass, instead of being a long-range force, electric interactions would become short-range “flypaper forces,” totally incapable of holding on to the distant valence electrons. Atoms, molecules and life are entirely dependent on the curious fact that the photon has no mass.[8]’

The trend in physics is that the number of cases of fine-tuning is growing over time. For example, physicist Joel Primack recently discovered an important link between the existence of dark matter and galaxy formation. Primack showed that “galaxies form only at high peaks of the dark matter density.“ Galaxies are generally thought to be necessary for life because they are critical for star formation. Thus, even aspects of physics which might seem pointless, such as dark matter, turn out to play an important role in making the universe more bio-friendly. I’ve also referenced an article in a previous blog that discusses how black holes “may actually account for Earth’s existence and habitability.[9]”

Any one of these facts by itself might just be seen as fortunate coincidences but there are enough of them to provide at least modest support for my fine-tuning claim:

“In the set of possible physical laws, parameters and initial conditions, the subset that permits rational conscious life is very small.”

The support is not as strong as what I documented based on our universe’s initial conditions nor as strong as what I will document concerning the fine-tuning of the constants of nature but it adds to the overall case. Moreover, this evidence has some bearing in the consideration of the multiverse[10] as an explanation of fine-tuning because it deals with physics at the level that most multiverse proposals cannot explain. In most multiverse scenarios the laws of physics are the same – what changes are the constants in the equations representing those laws. If you want to explore more about various multiverse alternatives, here is one useful perspective that was referenced in comments of a previous blog. Max Tegmark has proposed what he calls a level 4 multiverse in which all mathematical possibilities are realized somewhere in the multiverse. If we lived in such a multiverse, Occam’s Razor would not be a fruitful heuristic and we wouldn’t have Nobel laureates[11] talking about how simple, elegant theories led them to discoveries. There would be infinitely more equations with lots of complicated terms and expressions than there would be simple equations with minimal terms. Colombia professor Peter Woit provides a powerful critique of Tegmark’s highly speculative metaphysical proposal. These multiverse scenarios in which fundamental laws are different are not widely accepted among physicists.

In summary, life needs all of the 4 fundamental forces of nature and several principles from quantum mechanics. These facts about the laws support my fine-tuning claim that life-permitting physics is rare among possibilities. Standford physicist Leonard Susskind summarizes the physics well:

“It is gradually becoming accepted, by many theoretical physicists, that the Laws of Physics may not only be variable but are almost always deadly. In a sense the laws of nature are like East Coast weather: tremendously variable, almost always awful, but on rare occasions, perfectly lovely.[12]”

 

[1] Barnes, Luke. The Fine-Tuning of the Universe for Intelligent Life. Publications of the Astronomical Society of Australia, p. 18. http://arxiv.org/abs/1112.4647

[2] Ibid., p, 18.

[3] A supernova is an exploding star and is the key way heavy elements are distributed throughout the universe.

[4]Harnik R., Kribs G., Perez G., 2006, Physical Review D, 74, 035006

[5]Barnes, p. 46-7.

[6] Fermilab website. DOE. http://lbne.fnal.gov/why-neutrinos.shtml

[7] Here is a website if you want to explore this further: http://abyss.uoregon.edu/~js/cosmo/lectures/lec22.html

[8] Susskind, Leonard. The Cosmic Landscape, p. 174-5.

[9] http://www.scientificamerican.com/article/how-black-holes-shape-galaxies-stars-planets-around-them/

[10] If you missed my other blogs and are wondering what a ‘multiverse’ is, a multiverse is simply a collection of universes. If there is a vast ensemble of other universes with widely varying laws this might be a candidate explanation of the fine-tuning. Here was my blog on that topic: http://crossexamined.org/god-or-multiverse/

[11] For example, Eugene Wigner’s famous essay on The Unreasonable Effectiveness of Mathematics in the Natural Sciences. https://www.dartmouth.edu/~matc/MathDrama/reading/Wigner.html. Also, see how Weinberg regards beauty as a guide to finding the correct physical theories: http://www.pbs.org/wgbh/nova/elegant/view-weinberg.html. Or refer to this essay for a historical review: http://www.huffingtonpost.com/david-h-bailey/why-mathematics-matters_b_4794617.html

[12] Susskind, p. 90.

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Fine-Tuning of Initial Conditions to Support Life

This is the sixth blog in my series on fine-tuning. Here are the previous blogs if you missed them:

Intro/Philosophical Background

If You Don’t Want God, You Better Have a Multiverse!

How Does Fine-Tuning Provide Evidence for God?

Objections

Mistaken Objections that Seek to Trivialize Fine-Tuning

Important Objections in the Fine-Tuning Debate

But We Can’t Even Define Life

We’re finally ready to start exploring the fine-tuning data itself. A logical starting point is the initial conditions of our universe – are those which permit life rare among possibilities?

1)      Energy-Density is Finely-Tuned

The amount of matter (or more precisely energy density) in our universe at the Big Bang turns out to be finely-tuned to about 1 part in 1055. In other words, to get a life-permitting universe the amount of mass would have to be set to a precision of 55 decimal places. This fine-tuning arises because of the sensitivity to the initial conditions of the universe – the life-permitting density now is certainly much more flexible! If the initial energy density would have been slightly larger, gravity would have quickly slowed the expansion and then caused the universe to collapse too quickly for life to form. Conversely if the density were a tad smaller, the universe would have expanded too quickly for galaxies, stars, or planets to form. I argued in my previous blog that it’s implausible to expect life to originate without a long-lived, stable energy source such as a star. Thus, life would not be possible unless the density were just right – if you added or subtracted even just your own mass[1] to that of the universe this would have been catastrophic!

There is, however, a potential dynamical solution to this problem based on a rapid early expansion of the universe known as cosmic inflation. In this blog, I’ll be relying primarily on the most comprehensive review article on fine-tuning in the peer-reviewed literature – this one by Luke Barnes. I’ve referenced it previously and I’m hoping if I reference it enough I’ll get tech-savvy readers to check it out! It may be too technical for some readers and my blog can be viewed as just an attempt at explaining some highlights to non-physicists and tying it into my metaphysical hypothesis that God is the best explanation of the fine-tuning. So let’s look at what Luke Barnes has to say about inflation as a solution to the energy density problem. He points out 6 aspects of inflation that would have to be properly setup, some of which turn out to require fine-tuning. One significant aspect is that the inflation must last for the proper amount of time – inflation is posited to have been an extremely brief but hyper-fast expansion of the early universe. If inflation had lasted a fraction of a nanosecond longer, the entire universe would have been merely a thin hydrogen soup, unsuitable for life. Barnes cites an article by Max Tegmark of MIT that indicates that in a best case scenario about 1 in 1000 inflationary universes would avoid lasting too long. The biggest issue though seems to be that for inflation to start, it needs a very special/rare state of an extremely smooth energy density. Several articles make this point – consider Sean Carroll’s article:

“It is therefore a necessary (although not sufficient) condition for inflation to occur that perturbations be small at early times. . . . the fraction of realistic cosmologies that are eligible for inflation is therefore … 10-66,000,000.”

Barnes also explains why, even if inflation solves this fine-tuning problem, one should not expect new physics discoveries to do away with other cases of fine-tuning: “Inflation thus represents a very special case… This is not true of the vast majority of fine-tuning cases. There is no known physical scale waiting in the life-permitting range of the quark masses, fundamental force strengths or the dimensionality of spacetime. There can be no inflation-like dynamical solution to these fine-tuning problems because dynamical processes are blind to the requirements of intelligent life. What if, unbeknownst to us, there was such a fundamental parameter? It would need to fall into the life-permitting range. As such, we would be solving a fine-tuning problem by creating at least one more. And we would also need to posit a physical process able to dynamically drive the value of the quantity in our universe toward the new physical parameter.”

2)      Initial Conditions in a Very Low Entropy State

Even if inflation somehow could solve the energy density problem and scientists are mistaken that inflation requires its own fine-tuning, inflation doesn’t solve the problem with this next type of fine-tuning which relates to the universe’s initial entropy. What is entropy? Entropy represents the amount of disorder in a system. Thus, a high entropy state is highly disordered – think of a messy teenager’s room. Our universe began in an incredibly low entropy state. A more precision definition of entropy is that it represents the number of microscopic states that are macroscopically indistinguishable. An egg has higher entropy once broken because you’re “opening” up many more ways to arrange the molecules. There are more ways of arranging molecules that would still be deemed an omelet than there are ways to arrange the particles in an unbroken egg in where certain molecules are confined to subsets of the space in the egg – such as a membrane or the yolk. Entropy is thus closely associated with probability. If one is randomly arranging molecules, it’s much more likely to choose a high entropy state than a low entropy state. Randomly arranged molecules in an egg would much more likely look like an omelet that an unbroken egg.

Entropy can also be thought of as the amount of usable energy. Over time the usable energy decreases. This principle is known as the Second Law of Thermodynamics, which says that in a closed system the entropy on average increases until a state of equilibrium is reached. Thus, the Second Law predicts that our universe will eventually reach such a state of equilibrium or “heat death” in which nothing interesting happens. All life will die off long before such a state is reached. Life relies on usable energy from the environment.

It turns out that nearly all arrangements of particles in the early universe would have resulted in a lifeless universe of black holes. Tiny inconsistences in the particle arrangements would be acted on by gravity to grow in size. A positive feedback results since the clumps of particles have an even greater gravitational force on nearby particles. Penrose’s analysis shows that in the incredibly dense early universe, most arrangements of particles would have resulted basically in nothing but black holes. Life certainly can’t exist in such a universe because there would be no way to have self-replicating information systems. Possibly the brightest objects in the universe are quasars, which release radiation as bright as some galaxies due to matter falling into a supermassive black hole. The rotation rates near black holes and the extremely high-energy photons would disrupt information storage, a prerequisite for life[2].

Artist's impression of a stellar-mass black hole.Artist’s conception of a black hole. Credit: European Space Agency, NASA, and Felix Mirabel (the French Atomic Energy Commission & the Institute for Astronomy and Space Physics/Conicet of Argentina)

Oxford physicist Roger Penrose is the first scientist to quantify the fine-tuning necessary to have a low entropy universe to avoid such catastrophes. “In order to produce a universe resembling the one in which we live, the Creator would have to aim for an absurdly tiny volume of the phase space of possible universes, about 1/1010123 [3].” This number is incomprehensibly small – it represents 1 chance in 10 to the power of (10 to the power of 123). Writing this number in ordinal notational would require more zeroes than the number of subatomic particles in the observable universe, 10123 zeroes vs. about 1092 particles. Under the assumption of atheism, the particles in our universe would have been arranged randomly or at least not with respect to future implications for intelligent life. Nearly all such arrangements would not have been life-permitting so this fine-tuning evidence favors theism over atheism. We have a large but finite number of possible original states and rely on well-established statistical mechanics to assess the relevant probability.[4]

In a comment on one of in my earlier blogs, someone suggested that perhaps the universe is fine-tuned for black holes rather than life. The incredibly low entropy state of the initial conditions shows, however, that the exact opposite is true – fine-tuning was required to avoid excessive black holes! This fact about the initial conditions also calls into question Smolin’s proposed scenario that universes with differing physical constants might be birthed out of black holes. Smolin suggests the possibility of an almost Darwinian concept in which universes that produce more black holes therefore more baby universes than those which don’t. But if our universe requires statistically miraculous initial conditions to be life-permitting by avoiding excessive black holes, universes evolving to maximize black hole production would be unlikely to lead to life! (Even if the evolution of universes were possible)

Furthermore, the skeptic who thinks that black holes suggest a purposeless universe should consider that black holes can, in moderation and kept at distance, be helpful for life. While a universe comprised of mostly black holes would be life-prohibiting, having a large black hole at the center of a galaxy is actually quite helpful for life. Here is a Scientific American article that documents the benefits of Black Holes for life – it summarizes: “the matter-eating beast at the center of the Milky Way may actually account for Earth’s existence and habitability.”

Does inflation explain the low entropy of the early universe?

Here is how Sean Carroll answers this question: “Not by itself, no. To get inflation to start requires even lower-entropy initial conditions than those implied by the conventional Big Bang model. Inflation just makes the problem harder[5].” Penrose also has harsh words for inflation as an explanation of the low entropy state of the initial universe[6].

Barnes calls inflation a “cane toad solution” for the entropy fine-tuning. Cane toads were brought into Australia from Hawaii starting in 1935 to eat beetles threatening the sugarcane fields. With no natural predators in Australia this strategy was disastrous as these poisonous toads multiplied greatly and wreaked havoc on native species and the ecosystem in general. Thus, Barnes is saying that inflation makes this fine-tuning problem worse. None of this is to say that some version of inflationary theory isn’t true just that it doesn’t help this fine-tuning issue.

How well could a multiverse explain this evidence?

This is a key question to consider as we explore the fine-tuning evidence. If some features seem overly fine-tuned, this would be unexpected if our universe was simply a life-permitting universe randomly selected from a vast ensemble of other universes with other constants or initial conditions. A multiverse explanation for the fine-tuning of the low entropy fails miserably because this universe does seem to be finely-tuned much more than would be minimally necessary. As Penrose says: “We can get the solar system and all inhabitants for much less odds: 1 in 101060 .. These world ensemble hypotheses are worse than useless in explaining the anthropic fine-tuning of the universe.” In other words, Penrose argues that it would be more likely to just have the particles arranged in initial conditions such that you already have pre-formed intelligent life in a single solar system than to have such a large universe as ours in a low-entropy state that could eventually lead to intelligent life.

Even atheist Sean Carroll admits[7] that a multiverse explanation fails for this fine-tuning. First, he agrees with the widely-accepted principle I referenced above: “anthropically-selected parameters should be of the same order of magnitude as the largest value compatible with the existence of life.” He then explicitly agrees that the multiverse cannot by itself explain this particular fine-tuning and quotes Penrose’s numbers. “An example of fine‐tuning well beyond anthropic constraints is the initial state of the universe, often characterized in terms of its extremely low entropy… The entropy didn’t need to be nearly that low in order for life to come into existence. One way of thinking about this is to note that we certainly don’t need a hundred billion other galaxies in the universe in order for life to arise here on Earth; our single galaxy would have been fine, or for that matter a single solar system.” As an atheist he doesn’t view this as an insuperable problem, holding out hope that new physics could somehow explain this low entropy. Carroll indicates that he can’t think of any reason why God would fine-tune the universe more than is necessary, apparently not giving thought to the possibility that God might want to leave evidence that He setup the physics of the universe – evidence of the type that even an infinite multiverse cannot plausibly explain!

Is this evidence for God?

Even if this evidence points to design, why think that God is necessarily the designer?

If this is your perspective, please help remove the stigma on intelligent design so this type of evidence can be fairly evaluated. Also, note that this perspective affirms the claim of leading Intelligent Design advocates that design by itself does not necessarily prove God.

For this particular design evidence, however, I argue that we have reasons for thinking that only a supernatural being could setup these initial conditions in this way. Is it in principle physically possible for a being limited by the laws of physics to setup the initial conditions of our Big Bang? The Heisenberg Uncertainty principle limits our ability to even have knowledge of both position and momentum of particles beyond a certain scale – and it’s even more challenging to think about how so many particles might have their locations and velocities adjusted. The early universe would have been so small that the limits imposed by this physical principle would seem to prevent any physically-limited agent from making the necessary adjustments to the particles or even having knowledge to determine necessary adjustments. Moreover, even those who advocate a naturalistic cause to the Big Bang often admit that the Big Bang represents a spacetime boundary. Many theorists consider our universe to be a causally disconnected region of spacetime – which would make it impossible for a physically limited being residing in a different physical region from affecting anything in this new region of spacetime.
Thus, a supernatural designer seems more plausible than a natural designer. Also, if fine-tuning is required to bring about intelligent life, how did the first natural designers arise?

Does God Have to be Fine-tuned?

To me this seems like asking: “does an uncreated being depend on rare events or rare settings of physical parameters for His existence?” By definition God doesn’t rely on anything for his existence – this is the concept of a necessary being. If the concept of a necessary being seems implausible, I warn you that you might already believe premises that by the rules of logic would entail the existence of a necessary being. I invite you to explore that possibility in this online quiz.

[1] The universe is estimated to contain at least 10^80 atoms – here is one estimate of 10^53 kg: http://en.wikipedia.org/wiki/Observable_universe Anyone old enough to read this blog must weigh at least say 10 kg so this seems to be a safe estimate even after accounting for other forms of matter energy not included in the above mass.

[2] Refer to my previous blog for further justification: http://crossexamined.org/cant-even-define-life/

[3] Penrose, The Emperor’s New Mind, p. 343. He also makes the same argument in Road to Reality on p. 730.

[4] In addition, the entropy equation for a black hole, first developed by Bekenstein and Hawking, is involved in these computations. This equation is widely accepted by the physics community and I’ve read articles by those who believe in string theory and those who believe in loop quantum gravity arguing for their theories by pointing to how they can derive this same equation in their flavor of quantum gravity.

[5] Sean Carroll, http://preposterousuniverse.com/eternitytohere/faq.html

[6] Penrose says in Road to Reality, p. 755: “Indeed, it is fundamentally misconceived to explain why the universe is special in any particular respect by appealing to a thermalization process [such as inflation]. For, if the thermalization is actually doing anything (such as making temperatures in different regions more equal than they were before), then it represents a definite increasing of entropy. Thus, the universe would have had to be more special before the thermalization than after. This only serves to increase whatever difficulty we might have had previously in trying to come to terms with the initial extraordinarily special nature of the universe. . . . invoking arguments from thermalization, to address this particular problem [of the specialness of the universe], is worse than useless!” A couple of pages later Penrose also writes that “the point is that whether or not we actually have inflation, the physical possibility of an inflationary period is of no use whatever in attempts to ensure that evolution from a generic singularity will lead to a uniform (or spatially flat) universe.”

[7] Carroll, Does the Universe Need God? The Blackwell Companion to Science and Christianity. A copy is available online at http://preposterousuniverse.com/writings/dtung/.

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But We Can’t Even Define Life

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In my previous blog I addressed some important issues in making the case that fine-tuning supports theism over atheism. Today I want to look at the objection against fine-tuning that says we can’t assess fine-tuning claims because we can’t even define ‘life’ – or put another way: “fine-tuning claims don’t properly account for other possible life forms.” It has proven surprisingly hard for scientists to agree upon a definition for life. This uncertainty, however, hasn’t prevented biologists from making inferences about life nor has it kept physicists from writing numerous articles claiming that certain changes to physical constants would have resulted in a lifeless universe. In most cases, the inference to a lifeless universe is based upon severe catastrophes such as:

  • A very short-lived universe
  • No stable atoms
  • No chemistry
  • No long-lived sources of energy (such as stars)

It seems plausible that in these situations no life could arise of the kind that could evolve into intelligent, rational creatures. Many fine-tuning constraints involve multiple life-permitting criteria so that even if one of them was incorrect, there would still be other constraints on the life-permitting range of values based on different life-permitting criteria. John Leslie affirms that “many of the fundamental constants have to take the values they do for several independent reasons.” Moreover, even if half of the fine-tuning claims were mistaken there would still be a sufficient number of finely-tuned parameters to conclude that life-permitting universes are rare among possibilities. My fine-tuning claim is therefore robust since it doesn’t rely on all physicists’ claims being true – here it is again:

In the set of possible physical laws, parameters and initial conditions, the subset that permits rational conscious life is very small.

If some peer-reviewed articles are in error, there might be other articles defining other constraints or at least there would be enough remaining evidence to conclude that the life-permitting universes are rare among possibilities. But let’s look in detail at what is necessary for life according to scientists.

What are some essential attributes of any plausible life form?

Self-replicating

Any life form that could evolve to possess intelligence would have to include a self-replicating system. John von Neumann showed that any self-replicator requires certain features such as information storage and processing. Any information storage system would need to be comprised of reasonably stable entities. A star, for example, is a hot plasma of charged particles in rapidly changing configurations and thus is deemed implausible to store information needed to originate and sustain life. Also, in the near vacuum of space there are so few particles interacting that there is no plausible way to replicate enough information for complex life.

Non-trivial information content

As origin of life researcher Stuart Kauffman has noted: “all living things seem to have a minimal complexity below which it is impossible to go.” One theoretical estimate for the amount of information for the simplest possible life form is 113,000 base pairs.[1] Any life form is likely to require polymers of some type to serve as building blocks that can be replicated. There are multiple ways in which a lack of finely-tuned parameters could have prevented the formation of any atoms beyond hydrogen. In this scenario, there would be no polymers and indeed no chemical compounds except for H2. It is implausible to think that if only hydrogen ever existed in the universe that we would have intelligent life or so many physicists have argued.

Preservation of information content during replication

We also have some indications from our own planet of the importance of high fidelity information replication. The canonical genetic code that provides the mapping from RNA codons to amino acids used on our planet is highly optimized and arose early in life’s history[2] (else it wouldn’t be as universal.) Biologists interpret this as evidence of the importance of minimizing errors during translation and replication. The ability to preserve information is therefore recognized as being highly important for life.

Ability to harness energy from environment

Life must be able to harness energy from the environment or else the Second Law of Thermodynamics would pose an insurmountable hurdle. A long-lived stable energy source such as a star would therefore be required.

These same constraints and additional ones are described as prerequisites for life in an important article[3] in the Proceedings of the National Academy of Sciences (PNAS) that explains the attributes of alternate life forms that might eventually be found elsewhere in the universe. This article serves to confirm that the physics literature is making generous assumptions about what could be life-permitting. Here are some key points of the article with my comments provided after the quotations:

  1. “It is predictable that life, wherever we encounter it, will be composed of macromolecules.” I agree – information and storage would most likely require polymers of some type.
  2. “Only two of the natural atoms, carbon and silicon, are known to serve as the backbones of molecules sufficiently large to carry biological information.” I think that most physicists writing about fine-tuning are open to more alternatives than this article but the article raises some important points about the unique suitability of carbon:
    1. Carbon “unlike silicon … can readily engage in the formation of chemical bonds with many other atoms, thereby allowing for the chemical versatility required to conduct the reactions of biological metabolism and propagation. … Silicon, in contrast, interacts with only a few other atoms, and the large silicon molecules are monotonous compared with the combinatorial universe of organic macromolecules”
    2. “Life also must capture energy and transform that energy into the chemistry of replication. The electronic properties of carbon, unlike silicon, readily allow the formation of double or even triple bonds with other atoms.”
    3. “It is critical that organic reactions, in contrast to silicon-based reactions, are broadly amenable to aqueous conditions. Several of its properties indicate that water is likely to be the milieu for life anywhere in the universe.”
  3. “Life that depends only on chemical energy inevitably will fail as resources diminish and cannot be renewed.” This agrees with my point about needing a stable, long-term energy source to overcome the Second Law of Thermodynamics.
  4. “Temperature is a critical factor for life. Temperatures must be sufficiently high that reactions can occur, but not so high that that complex and relatively fragile biomolecules are destroyed. Moreover, because life probably depends universally on water, the temperature must be in a range for water to have the properties necessary for solute transfer.” Again I think that the physics literature is more open-minded in this aspect but certainly at some point it becomes too hot or too cold to either reliably store information or to have enough energy to replicate it.

But Does Life Have to be Carbon-Based Life?

My fine-tuning claim and that by prominent advocates such as Luke Barnes don’t presuppose that any life form would have to be carbon-based – it’s much more general than that. However, this PNAS article is one of many to claim that silicon is the best alternative to carbon as a basis for life. Silicon bears some similarities to carbon as expected from its position just below carbon on the periodic table. If we can understand why silicon-based life doesn’t appreciably increase the possibilities for life, then we can gain confidence in the generality of the fine-tuning claim.

As the PNAS article indicates, carbon is much more suitable for life than is silicon. Consider the specialness of carbon with regard to the number of types of molecules that can be formed with H (hydrogen) and the following elements[4]:

H – 1

He – 0

Li – 1

Be -1

B – 7

N- 7

O -2

Ne-0

C (carbon) – over 2300 known types of molecules just involving C and H

 Revisiting our dartboard analogy, consider how a life-permitting region is tiny among possibilities. As a reminder, just one finely-tuned parameter, the cosmological constant, has to be set in a narrow life-permitting region among possibilities that is comparable to hitting a bull’s-eye on a huge wall that is 376 million light-years per side. If the life-permitting region for carbon-based life is small, the region for silicon-based life should be smaller since silicon is less suitable for life than is carbon. Although there is one fine-tuning constraint that specifically references carbon, it turns out to also be applicable to silicon. Unless there was a nuclear resonance at just the right energy level, fusion in stars might have never produced carbon. However, without this resonance level there would be a bottleneck that would also inhibit silicon or elements heavier than carbon from being synthesized. Stars make carbon on the way to making silicon. (Most elements past beryllium were synthesized in stellar fusion from smaller atoms.) Thus, universes that produce silicon are no more likely than those that produce carbon – so the bull’s-eye for silicon-based life is smaller and basically just overlaps the carbon bull’s-eye.

Lessons Learned from Origin of Life Research

Consider how some origin of life researchers admit that the origin of the first life form from non-life is exceedingly improbable even with carbon and a diversity of other elements, long-lived stars, and other helpful attributes in our finely-tuned universe. For example, Christian Schwabe writes: “the formation of the first life is viewed as a chance process that occurred in spite of minuscule odds such as 1:10300 and which is accepted only because we are here.[5]“ Eugene Koonin appeals to the multiverse to overcome a horrendous improbability that he estimates at 10-1018 for a plausible first evolvable cell. Not all researchers are this pessimistic but the slow progress in the field should caution those who think that non-carbon life forms a large region in the space of possible parameters. If carbon is so clearly the best choice for life as most biologists believe and if the origin of life is somewhat of an unlikely event even utilizing organic (carbon-based) molecules such as RNA, how much more unlikely is a naturalistic origin of life without carbon.[6]

Fine-Tuning for Intelligent Life

Recall that my fine-tuning claim refers not to just any life form but to intelligent life. Since theism predicts that God would want some advanced life forms, this raises the bar for constraints on life-permitting universes. If merely primitive replicating cells could originate in somewhat less finely-tuned universe, this still would not count against my fine-tuning claim unless this life could also evolve to achieve intelligence and self-awareness. Clearly more fine-tuning is required for the universe to support rational conscious life than would be required for very primitive life forms.

Closing Thoughts

Most physicists writing about fine-tuning think that there are some very clear-cut cases of fine-tuning such as that for the cosmological constant. Consider, for example, how Nobel prize-winning physicist Steven Weinberg has argued for a multiverse explanation to the fine-tuning of the cosmological constant. He posits vast numbers of universes each with different values for the cosmological constant, the energy density of empty space. Weinberg’s argument for the value being consistent with multiverse predictions relies on a hard limit[7] for the life-permitting range so that our universe can be considered typical among life-permitting universes[8]. Smolin and others have critiqued his prediction as not being that close to what a multiverse would predict but that is irrelevant to my current point which is simply that Weinberg clearly believes that varying this constant by a tiny amount among the possibilities would result in no life of any kind living anywhere in that universe. Refer to my multiverse blog for why our universe would need to be typical among life-permitting universes for a plausible multiverse explanation.

Few physicists specializing in fine-tuning point to other possible forms of life as a supposed refutation to the fine-tuning argument but those who do should write rebuttals to the many peer-reviewed articles claiming life would not exist in certain scenarios involving different physical constants or initial conditions. Skeptics need to show why these authors were mistaken. Perhaps this is a good point of emphasis in urging physicists to be careful in their claims. If some of these fine-tuning claims are over-stated though this would actually provide evidence against a multiverse explanation to the fine-tuning because it would represent ways in which our universe is overly fine-tuned for life. A naturalistic multiverse predicts that our universe should not be more fine-tuned than is minimally necessary to support life.

 

[1] Forster A. C., et al. Nature Mol. Syst. Biol., 2 . doi:10.1038/msb4100090 (2006).

[2] Early Fixation of an Optimal Genetic Code. Molecular Biology and Evolution. Oxford Journals. Stephen J. Freeland2, et al.

[3] Pace, Norman. “The universal nature of biochemistry”. Proceedings of the National Academy of Sciences 98 (3) (2001): p. 805–8.

[4] This was presented by Luke Barnes at the Philosophy of Cosmology conference in 2013 in Santa Cruz, CA.

[5] Schwabe. Comparative Biochemistry and Physiology Part B: February 1994: (Volume 107, Issue 2) p. 167.

[6] In this blog, I have no intention of getting into discussions about whether or not we have evidence for divine intervention in the origin of life – that is a separate topic. Note that the origin of life and fine-tuning are separate issues. Fine-tuning deals with setting up an environment conducive to life – sort of like that biosphere they setup in Arizona. Conversely, origin of life relates to whether or not life forms were put into that biosphere or originated from non-living matter within it.

[7] By ‘hard limit’ I mean that no other life forms could exist anywhere in universes with cosmological constants whose absolute value exceeded a threshold that is about 120 orders of magnitude less than the natural values predicted by the Standard Model of Particle Physics. BTW, Weinberg first coined the term “Standard Model.”

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Important Objections in the Fine-Tuning Debate

In my previous blog I dealt with objections to fine-tuning based on misunderstandings of the nature of the argument or of probability theory. In this blog, however, I attempt to deal with important issues in the debate. If either objection succeeds it would undermine the design inference based upon the fine-tuning evidence.

Could the Laws of Physics Have Been Different?

If there is only one possible set of physics, then there is no sense in which the set of life-permitting physics could be said to be improbable. There are two aspects to considering with regard to whether or not the laws of physics might have been different.

1)      Are there other metaphysically possible alternatives?

Metaphysics is a branch of philosophy so this aspect is really a question that goes beyond science. However even among scientists, few think that there is only one logically possible set of laws of Nature. For example, in one of the classic fine-tuning papers Bernard Carr and Martin Rees note that “even if all apparently anthropic coincidences could be explained [in terms of some deeper theory], it would still be remarkable that the relationships dictated by physical theory happened also to be those propitious for life.[1]” Even if there was only one physically possible set of physics there is still something surprising about the fine-tuning evidence because there is no reason to think that their couldn’t have been different laws, constants, or initial conditions. If there really were no alternatives that were even metaphysically possible, one should be able to derive the laws and parameters of physics without even having to do observations and experiments but as physicist John Barrow notes in regard to the fundamental constants discussed in fine-tuning, “we have never successfully predicted the value of any dimensionless constant in advance of its measurement.”

If one looks at mathematical proofs, the premises are never based on empirical results whereas in science we’ve learned that we need to do experiments to choose among candidate theories. Metaphysicians, therefore, generally recognize that mathematical truths are true in all possible worlds (in the modal logic sense of the word) but that scientific truths are not.

Physicist Paul Davies responds to those few who have tried to argue that “the nature of the physical world would be entirely a consequence of logical and mathematical necessity. There would be no choice about it. I think this is demonstrably wrong. There is not a shred of evidence that the universe is logically necessary. Indeed, as a theoretical physicist I find it rather easy to imagine alternative universes that are logically consistent, and therefore equal contenders for reality.[2]”

2) Are there other physically possible alternatives?

Many leading physicists think that physics itself provides various potential means for varying the fundamental constants. Virtually every physics department is involved in research in theories such as String Theory that entail that the constants of physics actually could be different. As Lee Smolin explains, “string theory makes all the properties of the elementary particles contingent – determined not by fundamental law but by … solutions to the fundamental theory.[3]” String theory was once thought to be the best hope for a Theory of Everything which might explain why the constants of physics take on the values they do. Indeed it might greatly reduce the number of fundamental parameters. However, there seem to be a vast number of solutions to the equations of String Theory although they’re still not well-defined. Some scientists have complained that what was hoped to be a “Theory of Everything” has turned out to look more like a “Theory of Anything.”

In this article, physicist John Barrow lists 5 reasons to expect that the constants of physics can vary.

1)      “We know that the best candidates for unification of the forces of nature in a quantum gravitational environment only seem to exist in finite form if there are many more dimensions of space than the three that we are familiar with. This means that the true constants of nature are defined in higher dimensions and the three-dimensional shadows we observe are no longer fundamental and do not need to be constant. Any slow change in the scale of the extra dimensions would be revealed by measurable changes in our three-dimensional ‘constants’.”

2)      “Some apparent constant might be determined partially or completely by spontaneous symmetry-breaking processes in the very early universe. This introduces an irreducibly random element into the values of those constants.”

3)      “Any outcome of a theory of quantum gravity will be intrinsically probabilistic… [thus some constants are] predicted to be spatial random variables”

4)      “A non-uniqueness of the vacuum state for the universe would allow other numerical combinations of the constants to have occurred in different places.”

5)      There are some observations that the fine-structure constant may have varied very slightly over time and/or space. [Newer studies are still not conclusive on this point – the data is somewhat ambiguous.]

 Even if the constants and laws of physics couldn’t vary, there is even more reason to think that there were many physically possible sets of initial conditions. Paul Davies states this emphatically:

“Even if the laws of physics were unique, it doesn’t follow that the physical universe itself is unique…the laws of physics must be augmented by cosmic initial conditions…there is nothing in present ideas about ‘laws of initial conditions’ remotely to suggest that their consistency with the laws of physics would imply uniqueness. Far from it…it seems, then, that the physical universe does not have to be the way it is: it could have been otherwise.[4]”

John A. Wheeler agrees: “Never has physics come up with a way to tell with what initial conditions the universe was started off. On nothing is physics clearer than what is not physics.”

What about the laws themselves varying?

Fine-tuning proponents don’t generally seek to quantify the rarity of life-permitting physics among all possible laws but rather at the level of initial conditions and constants as not enough is known to evaluate that case in any detail. As Robin Collins puts it, fine-tuning only considers the epistemically illumined region. As we evaluate the space of possibilities that we have sufficient “light” to evaluate, we discover the remarkable fact that life is only possible in a very small subset. Going back to our dartboard analogy from a previous blog, we have some uncertainty about the size of the wall – maybe it’s not 300+ million light years per dimension or maybe it’s actually larger. The argument is still quite powerful even if we’re over estimating the range of available parameters by a factor of a million million million – and remember this analogy dealt with only one of the many finely-tuned parameters.

In a future blog, I will examine how life depends upon certain laws and principles but will not attempt to make a numerical probabilistic case in that arena. In many candidate physical theories, the laws themselves wouldn’t change in different universes, merely the constants in the equations for those laws.

But We Can’t Assess Exact Probabilities

Another objection is that we can’t assess an exact improbability for life. We can tell something is highly improbable even if we cannot compute an exact value or conduct a series of trial experiments. What are the odds that I would beat Lebron James in a one-on-one basketball game? My only chance would be if he got hurt or something and it would be hard to estimate that very precisely.

I agree that it is premature to put an exact number to the rarity of life-permitting universes among possibilities but I believe that we have a dozen or more independent reasons for thinking it highly improbable. I did toss out the improbability of 1 in 10^100 in a previous blog – as a counterfactual saying in effect that if it could be shown that intelligent life was this rare among possibilities, wouldn’t you count it as some evidence for cosmic design? I indicated that when I present the evidence in detail that I would attempt to justify this number and that many non-theistic physicists accept this magnitude of a number for just a single parameter in some cases.

If we accept the plausible assumptions found in the peer-reviewed physics literature, we do end up with an incredible improbability for a life-permitting universe if physics is set randomly. These articles often cite a natural range for constants based on magnitudes derived from Quantum Field Theory or particle masses as predicted by the standard model of particle physics. For my fine-tuning claim to be defeated virtually all of these physics articles would need to be mistaken.

Computing an exact value involves knowing the exact range of possibilities and the distribution function neither of which is generally known precisely. Many scientists take the principle of indifference to imply a uniform (and thus linear) distribution of possible values for constants, Citing Aguirre’s work, Luke Barnes indicates that it’s unreasonable to expect that new information about underlying physics will invalidate fine-tuning: “In short, to significantly change the probability of a life-permitting universe, we would need a prior that centres close to the observed value, and has a narrow peak. But this simply exchanges one fine-tuning for two – the centre and peak of the distribution.” Barnes/Aguirre discussed this at last summer’s philosophy of cosmology conference amidst many prominent physicists and philosophers who have written about the fine-tuning and no one challenged it. Barnes lists some other key attendees as: Craig Callender (UCSD), Sean Carroll (Cal Tech), Shelly Goldstein (Rutgers), Anna Ijjas (Harvard/Rutgers), Tim Maudlin (NYU), Priya Natarajan (Yale), Ward Struyve (Rutgers), Tiziana Vistarini, (Rutgers), David Wallace (Oxford), Alex Pruss, Chris Smeenk, Fred Adams, Leonard Susskind, Matt Johnson.

In summary, I think it would be a mistake to ignore fine-tuning simply because we don’t know exact ranges that values can take on – if anything we may be underestimating them. As I’m presenting the evidence I’ll try to highlight what physicists are saying with regard to expectations for the range of parameter space and the reader can evaluate whether or not these physicists are mistaken in claiming that life-permitting universes are rare among possibilities.

[1] Bernard Carr and Martin Rees, “The Anthropic Principle and the Structure of the Physical World,” Nature 278, (1979): 612.

[2] Paul Davies in Templeton address in August 1995. http://www.firstthings.com/article/1995/08/003-physics-and-the-mind-of-god-the-templeton-prize-address-24

[3] Smolin. The Trouble with Physics: The Rise of String Theory, the Fall of a Science, and What Comes Next. (New York: Houghton Mifflin Co., 2006), p. 127.

[4] Paul Davies, The Mind of God (New York: Simon & Schuster, 1992), p 169.

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Mistaken Objections that Seek to Trivialize Fine-Tuning

This is my third blog in a series on fine-tuning as evidence for God. Here are the first and second blogs, which deal with the philosophical background. Before I share the evidence I want to refute or at least rebut a few objections seen at the popular level but rarely in scholarly circles – otherwise, readers might just ignore the argument no matter what fine-tuning evidence is presented. Generally one should be wary of dismissive claims that attempt to trivialize what many intelligent physicists and philosophers think is worthy of discussion and evaluation. Even hardened skeptics admit that the fine-tuning evidence is worth evaluating. The late Christopher Hitchens answered a question concerning what is the best argument from the other side: “I think everyone of us picks the fine-tuning one as the most intriguing… you have to spend time thinking about it, working on it. It’s not a trivial [argument].” But let’s consider some popular level responses that seek to trivialize fine-tuning.

The Universe is not Adapted to Us, We’re Adapted to the Universe

This was the primary response given by atheist philosopher Peter Boghossian when I discussed fine-tuning in his recent Q&A session at UT Dallas. This response is based on a fundamental misunderstanding of the articles in the physics literature as addressed in my previous blog. The fine-tuning deals with how the physics has to be setup before life gets started so without fine-tuning there is no evolutionary way for adapting life to the universe.

Aren’t Any Set of Physical Constants Just As Likely As Any Other?

About 5 years ago I had the opportunity to engage in sort of a friendly debate with the head of the science department at the high school where my daughter and son attended. She was taking a “Theory of Knowledge” class as part of the International Baccalaureate curriculum and the instructor needed to provide an example to students of presentations of opposing viewpoints. He had heard that I was an advocate of Intelligent Design and wanted each of us to make presentations supporting our viewpoints. He is an excellent teacher and heads the science department and I was somewhat nervous to be engaging in my first public debate of this type – this was before I had read a dozen or so books on fine-tuning and taken a graduate course on Cosmology. However, the instructor gave a surprisingly weak response to the fine-tuning evidence that I had presented. He set up an analogy for the students of dealing out a set of 5 cards from a set of 10 packs of cards with different backings. The odds of dealing out any particular hand were extraordinarily low but he argued that since any set of cards was just as likely as any other set, no inference could be made that the cards were not dealt at random. This was supposed to refute a design inference because any set of constants of physics is just as likely as any other.

However, the assumption that any set of constants is just as likely as any other is the very thing that we want to know. Starting off with that as an assumption begs the question against design. As Luke Barnes articulates in this excellent podcast dealing with responses to the fine-tuning claim, suppose we’re playing poker and every time I deal I get a royal flush. If this continues to happen, you become increasingly convinced that I’m likely to be cheating. If I responded to an accusation of cheating by just saying “well any set of 5 cards is just as likely as any other so you can’t accuse me of cheating” you would be rational to reject this explanation. The question is not “how likely is any set of 5 cards?” but rather “how likely is it I’m cheating if I just dealt myself 10 straight royal flushes?” This question accounts for the possibility that I’m cheating which would almost certainly be true in this scenario. So the right question is “given the fine-tuning evidence, how likely is it that the constants were set at random?” The values for physical constants conform to a very particular pattern – that which supports life. The fact that we have so many finely-tuned constants makes it unlikely that they were all set at random (at least in the single universe scenario and I’ve already shown some of the problems/challenges in multiverse explanations.)

Puddle Thinking

Another failed objection to Fine-Tuning is based on something written by Douglas Adams, the well known author of Hitchhiker’s Guide to the Galaxy (although this quote is not from that book):

“Imagine a puddle waking up one morning and thinking, ‘This is an interesting world I find myself in, an interesting hole I find myself in, fits me rather neatly, doesn’t it? In fact, it fits me staggeringly well, must have been made to have me in it!’”

Richard Dawkins applied this to the fine-tuning at Adams’ eulogy. There is a meaningful lesson perhaps in this analogy but it’s not applicable to the fine-tuning. In the analogy, “gradually, the puddle gets smaller and smaller” but the water still conforms the hole perfectly up to a certain height. If we discovered that any set of constants and initial conditions would permit life, then the puddle analogy would be applicable but since the universe has to be fine-tuned to support life, it’s quite disanalogous! Any configuration of dirt supports water whereas very, very few configurations of physics can support life. Some skeptical scientists who have studied the fine-tuning explicitly state this analogy “doesn’t hold water” – such as David Deutsch.

Improbable Events Happen All the Time

Yeah, but when a series of unlikely events have something in common that is predicted by a hypothesis one generally treats that as evidence for the hypothesis. There are many cases in science where inferences are made based on probabilities. Certain organisms, for example, are considered to be evolutionary descendants because it would be extremely unlikely for unrelated organisms to randomly arrive at the same DNA sequences (from a naturalistic perspective anyway). Unlikely events or states conform to a pattern predicted by the hypothesis of common descent.

In the fine-tuning case, a series of fundamental constant of physics such as various particle masses and force strengths all happen to take on values in a narrow range that permits life. These facts conform to a long-standing hypothesis that God would want to create a life-permitting universe and leave evidence that He created it and thus fine-tuning should be treated as evidence for design.

Just one Universe so Probability of Life Must be 1 out of 1

This response implies a frequentist view of probability whereas my fine-tuning argument deals with a Bayesian approach to probability which deals with epistemic probability (as a degree in belief). Refer to this article in the Stanford Encyclopedia for some issues in the finite frequentism version of probability theory – it might be useful in some contexts but there are many cases in science where we would be unable to make reasonable inferences without a more generalized approach to probability theory. For example, if scientists are reasoning about what caused the disappearance of the dinosaurs, finite frequentism is not a useful tool for analyzing this one-time event. There are also many cases in theoretical physics in which we can compute probabilities for certain events and don’t need to rely solely on past statistics. Suppose we have just created the first ever 20-sided die (an icosahedron with numbered sides). Under the finite frequentist approach, suppose we roll the die one time and obtain a 7, should we assume the probability of rolling 7’s is 1 out of 1? We can do better using theoretical physics and recognize that we have a 1/20th chance of rolling each number if the die is perfectly constructed. In engineering, we frequently assess theoretical probabilities before deciding what to build.

Consider an example from theoretical physics – we can know that universes in which the electromagnetic force is stronger than the strong nuclear force will likely be lifeless without having to find such a universe and test it for the presence of life. In such a universe there would be no stable atoms and thus no way of plausibly storing enough information to support a self-replicating system. As Luke Barnes says, analyzing fine-tuning is “not just like theoretical physics, it is theoretical physics.” He also has an excellent blog dealing with the limitations of finite frequentism.

Irrelevant Objections

A common objection is that the universe is not jam packed with life, therefore the universe is not-fine-tuned for life” or that “we can’t live in most parts of the universe so it’s not fine-tuned for life.” Note that these objections are very human-centric whereas in Christian theology God not humans is the most important thing in the universe. In my introductory blog, these kinds of overly narrow expectations of what God would or wouldn’t do are what I caution against. The logical approach for a skeptic would be to assess whether or not God exists in an open-minded way and then seek out more information about His attributes. A God that is not merely a human creation should differ at least slightly from human expectations. In terms of these particular objections, God may simply want to humble humans and show us how small and powerless we are compared to Him. More importantly though, these objections are irrelevant to the fine-tuning claim that I made:

“In the set of possible physical laws, parameters and initial conditions, the subset that permits rational conscious life is very small.”

Moreover, as Barnes points out – if you can understand why humans can’t live in these other parts of the universe such as the vacuum of space or near a black hole you can understand why the universe needs to be finely-tuned because without such fine-tuning the entire universe would be a near vacuum or too full of black holes for life. So in some sense these objections implicitly affirm the fine-tuning claim.

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How Does Fine-tuning Provide Evidence for God?

In my previous blog, I defined the following fine-tuning claim:

“In the set of possible physical laws, parameters and initial conditions, the subset that permits rational conscious life is very small.”

I pointed out how this fine-tuning claim is widely accepted within the physics community and that some skeptics even admit that it’s not unreasonable to view this as evidence for cosmic design if there are not a multitude of other universes with different randomly-set constants. In this blog I’ll make a philosophical case that the fine-tuning of the universe for life constitutes evidence for God.

Let’s apply a methodology commonly used in science for making an inference to the best explanation.1 Scientists frequently evaluate candidate models based on how well predictions of those models match observations. In an atheistic origins model, the constants governing the laws of physics and the initial conditions were either set randomly or at least without respect to their consequences for bringing about intelligent life. In a theistic model, however, it’s not surprising to think that God would prefer a universe which supports rational conscious creatures. The skeptic who raises the problem of evil as an objection to God’s existence is implicitly affirming this expectation that God should favor conscious life. 2

Another expectation of skeptics also supports the inference from fine-tuning to divine design – the claim that God should leave some evidence for his existence. It is unsurprising that God would want to create a universe in which it appears that initial conditions and laws were set up providentially to reveal a purpose for the universe. If nearly any set of constants would have resulted in intelligent life, then it would appear as though no intervention was required to setup life-supporting physics. Conversely under atheism, there is no reason to expect that a life-supporting universe would be unlikely among possibilities. Indeed many skeptical scientists who have studied this fine-tuning data admit its surprising nature under their worldview. David Deutsch, for example, writes: “If anyone claims not to be surprised by the special features that the universe has, he is hiding his head in the sand. These special features are surprising and unlikely.”

Fine-tuning, if true, therefore, favors the hypothesis of theism over atheism because this data is much more likely on theism than atheism. This falls out from the likelihood principle from Bayesian probability theory. We can examine fine-tuning in isolation to see how one should adjust the credence for inferring God’s existence. My claim is simply that whatever was one’s prior epistemic probability for God’s existence, this fine-tuning evidence should make the hypothesis that God exists epistemically more likely than previously thought. So I’m not claiming proof of God’s existence but rather that fine-tuning is evidence for God’s existence.

Even many agnostics or atheists seem to agree that at least prima facie the fine-tuning looks like divine design. The fine-tuning is one of the key lines of evidence that led philosopher Antony Flew to renounce his long-held atheism. Here are a few quotes capturing the reaction among prominent skeptics that have studied this evidence:

“The impression of design is overwhelming. 3” Physicist Paul Davies

“A common sense interpretation of the facts suggests that a superintellect has monkeyed with physics … and that there are no blind forces in nature.4” Physicist Fred Hoyle

“As we survey all the evidence, the thought insistently arises that some supernatural agency – or, rather, Agency – must be involved. Is it possible that suddenly, without intending to, we have stumbled upon scientific proof of the existence of a Supreme Being? Was it God who stepped in and so providentially crafted the cosmos for our benefit?5” Astronomer George Greenstein

“Luck in the precise form and nature of fundamental physical law is a different kind of luck from the luck we find in environmental factors. It cannot be so easily explained, and has far deeper physical and philosophical implications. Our universe and its laws appear to have a design that both is tailor-made to support us and, if we are to exist, leaves little room for alteration.6” Stephen Hawking. He also says that the fine-tuning may reveal “a divine purpose in Creation and the choice of the laws of science.” To be clear, Hawking ultimately rejects this interpretation but admits the facts seem to support this viewpoint if there were no multiverse.

“If there is an inexplicable coincidence in the fundamental constants of nature whose values have to be precisely-tuned within a wide range of otherwise available possibilities that would make a complex universe possible then this constitutes a phenomenon that very naturally invites explanation in terms of a cosmic scale designer.” Oxford Philosopher Peter Millican  in his debate with William Lane Craig. Millican rejects the conclusion of design but seems to agree with my argument thus far that if the universe is fine-tuned it should serve as evidence for God.

The Philosophical Basis of a Fine-Tuning Argument for God

My philosophical argument is based on philosopher of science John T. Roberts’ formulation. The existence of life is treated as “background knowledge while the fact that fine-tuning is required for life serves as the evidence.” Roberts has an excellent illustration to elucidate the argument. Suppose that you witness a dart coming from behind you and landing on an enormously large wall that is homogeneously white. You wonder whether the dart was skillfully aimed or just flung in a random direction. You might be tempted to think that the dart was aimed since it’s incredibly improbable to have landed at that particular point on this enormous wall but that would be mistaken. There is nothing to distinguish the dart’s landing spot from any other location. Suppose that you then put on a pair of infrared goggles and see that there is actually a single, tiny bull’s-eye surrounding the dart on the wall. Now an inference that the dart was aimed seems plausible.

infraredDartGray

Picture (courtesy of Richard Matthews)

 One can easily see how this analogy applies to the fine-tuning. Whether or not the dart was aimed is analogous to the question of whether or not there was intent in the setup of physics. No one argued for design based on the particular constants of physics until knowledge was gained that there was something special about those constants – life-permitting values were enormously rare. There was no significance at all in recognizing that constants permitted life – the perception of specialness arose when the set of life-permitting values were discovered to be a miniscule subset among possibilities. A universe containing life would be an aim-worthy target for a Creator. Most fine-tuning advocates run an argument for theism based on God favoring a life-permitting Universe but Roberts’ way of framing the argument side-steps certain objections as will be seen in future blogs.

Some readers may not be seeing the full force of the argument because I haven’t yet presented the extensive evidence that the universe is finely-tuned. Consider that many different parameters must each be finely-tuned – so it’s really like having many darts each hit a bull’s-eye. The inference to design will be more easily recognized if we shed some light as to the specialness of the required values. Consider the size of the bull’s eye and wall based on just 1 parameter – the cosmological constant. There is a natural range for possible values for this constant because there are known contributions that are 10120 times larger than the overall net value. (There is a near perfect but inexact cancellation of contributions accurate to 120 decimal places). Let’s use the most conservative numbers in the physics literature that indicate a fine-tuning to 1 part in 1053. If the cosmological constant, which governs the expansion rate of the universe, had been larger than its current value by this tiny fraction, then the universe would have expanded so fast that no stars or planets would have formed and therefore no life. If the value were smaller by this amount then the universe would have rapidly collapsed before the universe cooled sufficiently to allow for stable information storage which is required by any self-replicating system such as life. (And could intelligent life really emerge if the universe lasted only a few days even under ideal conditions?) Using this ratio, the size of the wall containing a single inner bull’s-eye of the size on a standard dart board, would be over 376 million light years on each side. A light-year is the distance light travels in a year – at 186,282 miles per second this is pretty far. The inference that the dart was aimed to the special area where life is possible seems reasonable – and that is just considering one of the finely-tuned parameters!

For one who assumes that nature is all there is, it is very surprising that the universe began in such an improbable state that it could support life and that a number of fundamental parameters whose values are not dictated by any known underlying theory all happen to lie in a narrow life-permitting region. This should cause one to question the assumptions of the naturalistic worldview.

1To clarify, I’m not making a scientific argument but rather a philosophical argument which relies on scientific data to affirm the truth of the premise that life-permitting universes are rare among possibilities.
2Refer to writings by Alvin Plantiga and William Lane Craig and others on the problem of evil as it’s tangential to my fine-tuning argument.
3Davies, The Cosmic Code, p. 203.
4Fred Hoyle, “The Universe: Past and Present Reflections.” Engineering and Science, Nov 1981. pp. 8–12
5Greenstein, George. The Symbiotic Universe, p.27.
6Hawking, Stephen. Grand Design, p. 162.

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If You Don’t Want God, You Better Have a Multiverse!

If You Don’t Want God, You Better Have a Multiverse!

Such is the advice from Bernard Carr in grappling with the fascinating discovery that the physics of the universe had to be fine-tuned if it were to support life. Carr views the only viable options as being either God or a multiverse (the theory that there are a vast number of other universes). Stanford physicist Leonard Susskind also calls our attention to these relatively recent discoveries: “Science may be undergoing a huge course correction, a paradigm shift. A titanic controversy has erupted over the strange anthropic pattern that nature seems to exhibit – the pattern of extraordinary unexplained coincidences that are necessary for our own existence.[1]” I will discuss these fine-tuning discoveries and their implications in a series of blogs as part of my ongoing series on scientific evidence for God.

Here are my previous blogs in this series prior to the recent hiatus:

Philosophy

Can Science Disprove God?
What Counts as Evidence for God from Science?

Evidence for God from the Origin of the Universe:

Origin of the Universe

Doesn’t Quantum Mechanics Violate the Causal Principle?

Much Ado About Nothing

Philosophical Arguments that the Universe had a Beginning

 Before presenting the actual fine-tuning scientific data, I want to explore the philosophical basis of the argument. We can then examine the scientific data relative to some reasonable evaluation criteria.

What is Fine-Tuning?

Fine-tuning is not a synonym for design but is rather a technical term in physics that refers to a narrow range for suitable values among possibilities. All else being equal, if theory A requires fine-tuning and theory B doesn’t, then theory B is deemed to be more likely to be true because it doesn’t rely on assumptions for narrow constraints for the values of one or more parameters. There are other contexts where fine-tuning is discussed with respect to various hypotheses having nothing to do with life, but I defend this fine-tuning claim:

“In the set of possible physical laws, parameters and initial conditions, the subset that permits rational conscious life is very small.”

The universe is said to be finely-tuned for life if most possible ways for setting up physics would have resulted in no intelligent life anywhere in the universe. My claim is close to that defined by Luke Barnes[2] in his important review article. I use the term “rational conscious life” rather than “the evolution of intelligent life” because the fine-tuning claim can be evaluated independently of biological evolution. My wording also reflects Christian expectations that God wanted creatures in His image – rational, conscious creatures with whom He could have a relationship.

It’s important to note that my fine-tuning claim deals with the fundamental physics of the universe required before any biological evolution could get started. I personally happen to be skeptical of the all-encompassing claims about naturalistic macroevolution but even if it explains the full diversity of life that is irrelevant to my fine-tuning claim. For example, a universe without one type of fine-tuning would have lasted only a few hours and never cooled below 9000K. Thus, it is unreasonable to expect such a universe to have contained life – much less intelligent life. Physicists writing fine-tuning articles routinely make claims about life being impossible without certain finely-tuned parameters or initial conditions. Craig Hogan, for example, is very explicit, stating that “changing the quark masses even a small amount has drastic consequences [for] which no amount of Darwinian selection can compensate.” Alan Lightman of MIT clarifies the nature of the fine-tuning: “if these fundamental parameters were much different from what they are, it is not only human beings that would not exist but no life of any kind would exist.” No biological evolution can start until you have the first living cell and the vast majority of ways to setup the physics never allow life to get started.

My future blogs will detail some of the evidence supporting my fine-tuning claim but here is a foretaste from atheist physicist Stephen Hawking’s best-selling book, A Brief History of Time (on p. 125):

“The remarkable fact is that the values of these numbers [i.e. the constants of physics] seem to have been very finely adjusted to make possible the development of life. For example, if the electric charge of the electron had been only slightly different, stars would have been unable to burn hydrogen and helium, or else they would not have exploded. It seems clear that there are relatively few ranges of values for the numbers [i.e. the constants of nature] that would allow for development of any form of intelligent life.”

How widespread is the acceptance of fine-tuning among physicists?

In a word – very! In my years of researching this topic, I’m amazed at how few scientists who have studied the fine-tuning details disagree with this core claim that the subset of life-permitting physics is a tiny fraction among possibilities. Since Luke Barnes is a top researcher on this topic, consider his input on the level of acceptance of the fine-tuning claim: “I’ve published a review of the scientific literature, 200+ papers, and I can only think of a handful that oppose this conclusion, and piles and piles that support it.[3]”

Of course, any topic with potentially significant philosophical or even spiritual implications is likely to encounter some opposition. Many physicists who accept the fine-tuning data do not, of course, embrace the design implications. Some readers might be wondering how the skeptics interpret this evidence. The most common response among skeptical physicists is an appeal to the multiverse as alluded to in the introduction.

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Image: Courtesy Kevin Hainline

Is the multiverse a satisfying explanation of the fine-tuning?

If we have an enormous number of other universes and if they have widely varying laws, then perhaps sufficient probabilistic resources exist for life to emerge in some universe. We need to carefully evaluate how well the multiverse serves as a potential explanation for fine-tuning. Here are some potential challenges to a multiverse explanation of the fine-tuning:

– No empirical evidence exists for any universe other than our own

– We need vast numbers of other universes to overcome horrendous odds against a life-permitting universe – probably more than 10100 (which is more than the number of subatomic particles in our observable universe)

– A universe generating mechanism might itself require fine-tuning to generate so many universes o This is certainly true for the most popular multiverse theory – eternal inflation.

♦ Sean Carroll admits[4] that “inflation only occurs in a negligibly small fraction of cosmological histories, less than 10-66,000,000.”

o Also, other assumptions are required for eternal inflation – as Vilenkin admits: “The most likely thing to pop out of the [quantum vacuum] is a tiny Planck-sized universe, which would not tunnel, but would instantly recollapse and disappear. Tunneling to a larger size has a small probability and therefore requires a large number of trials. It appears to be consistent only with the Everett interpretation.” This Everett or many-worlds interpretation of quantum physics is one of a dozen or so interpretations and many physicists are skeptical of this interpretation because it entails that parallel universes are spawned at every quantum event.

–  The new universes would need to have different physical constants

o There are many theoretical reasons for thinking constants might vary but we have no clear evidence that fundamental constants have ever been more than trivially different in different parts of our observable universe. Without new physics in each universe, our odds for life wouldn’t be helped – it’d be like buying a million lottery tickets with the same set of numbers for each ticket!

–  The constants would need to vary extremely widely

o The degree of variety in possible values for the constants may not be sufficient unless a particular version of string theory is true. Some string theorists think that perhaps there are as many as 10500 different possible values for the constants. This variance would be more than sufficient. Polchinski, however, is one of many string theorists who disagree with this proposal – “there is no reason to expect … a large number of variations in the constants of physics.[5]”

♦ A significant minority segment of the physics community is highly skeptical of any version of String Theory because it thus far has no clear empirical confirmation and a history of failed predictions.

– It is fallacious to view the fine-tuning itself as evidence for a multiverse since the existence of other universes doesn’t make it any more likely that our universe supports life. We need independent evidence for the multiverse hypothesis before it becomes a viable candidate explanation of the fine-tuning. MIT philosopher of science Roger White shows this using Bayesian logic and summarizes: “the fact that our universe is fine-tuned gives us no further reason to suppose that there are universes other than ours.”

– Is the multiverse theory even scientific?

o Personally I’m not too concerned about this question – we just want to follow the evidence wherever it leads even if that is beyond the realm of direct empirical confirmation. It should be pointed out though that the most popular multiverse theories, such as eternal inflation, postulate other universes that could not have interacted with our universe, even in principle. About the only way to affirm such multiverse theories is to examine how well our universe conforms to multiverse predictions after applying a selection effect due to the constraint that observers can only observe a life-permitting universe. This selection effect is known as the anthropic principle although it really deals with any type of observer whereas ‘anthropic’ is derived from the Greek word ‘anthropos,’ which means human.

o Thus, our universe should be typical among life-permitting universes. If our universe appears “overly” fine-tuned it would still look more like the product of design than a random member of an ensemble of life-permitting universes. For further information about this widely accepted principle among multiverse advocates, see this excellent book of essays by prominent physicists entitled Universe or Multiverse?

♦ Many scientists are highly critical of this approach of trying to indirectly affirm the multiverse. However, some skeptical scientists seem willing to accept this approach because it seems to be the only way to avoid the design implications of the fine-tuning. Polchinski, a leading string theorist, acknowledges that “anthropic reasoning runs so much against the historic goals of theoretical physics that I resisted it long after realizing its likely necessity. But now I have come out.”[6] Susskind claims that “the stakes are to accept the [string] landscape and the dilution in the scientific method it implies or give up science altogether and accept intelligent design (ID) as the explanation for the choices of parameters of the standard model.”[7]

As we’re examining the fine-tuning evidence in future blogs, I’ll point out cases where parameters are significantly more fine-tuned than is necessary since this counts against the multiverse as a solution to the fine-tuning problem. As a preview consider that many physicists such as Lee Smolin have pointed out problems in this arena such as proton decay rates being many orders of magnitude smaller than the life permitting region. Also, Oxford physicist Roger Penrose says that the multiverse is “worse than useless” as explanation of the finely-tuned initial conditions because the multiverse predicts hyper-exponentially more tiny universes than large ones like ours.

Some physicists have rightly pointed out that a multiverse by itself is not necessarily a violation of Occam’s razor since it could arise from a simple law-like mechanism for generating universes. The key issue though is that for the multiverse to be an adequate explanation for the fine-tuning it requires the conjunction of several hypotheses for which we lack any empirical evidence:

  1. A universe-generating mechanism that generates a plethora of universes
  2. That this mechanism doesn’t itself require fine-tuning
  3. The many-worlds interpretation of quantum physics
  4. The ability to widely vary constants in those universes. If you think that it’s a foregone conclusion that String Theory/M-Theory[8] will come to the rescue in this area, you should watch this video clip by Oxford physicist Roger Penrose where he exclaims that “it’s not even a theory … it’s a collection of hopes”.

Occam’s razor therefore does seem to favor design over the multiverse. When one accounts for the extensive problems in affirming premise 2 and how these multiverse theories make predictions incompatible with our universe, the hypothesis that God designed the physics of the universe to bring about life is more plausible. That so many physicists appeal to the multiverse to explain away the design implications of fine-tuning testifies to the power of this argument!

Notes

[1] Susskind, The Cosmic Landscape: String Theory and the Illusion of Intelligent Design. The Chattahoochee Review Podcast. (near about the 6th minute)

[2] I highly recommend Barnes’ excellent blogs correcting various people on both sides of the debate when they make mistakes in their analysis of the math, physics, or philosophy. I hope I can get more people to read his blogs. I recommend his blogs more than my own – I’m just trying to be a popularizer of the excellent scholarly work that is out there!

[3] To support the claim that Barnes is a top researcher/thinker on fine-tuning consider that he was invited to speak at last summer’s Philosophy of Cosmology conference. Here is his blog article from which I obtained his quote: http://letterstonature.wordpress.com/2013/12/23/christmas-tripe-a-fine-tuned-critique-of-richard-carrier-part-3/

[4] Carroll, Tam. Unitary Evolution and Cosmological Fine-Tuning. http://arxiv.org/abs/1007.1417v1

[5] Polchinski, String Theory. (1998, Vol. 2, pp. 372-73).

[6] Lee Smolin. The Trouble with Physics: The Rise of String Theory, the Fall of a Science, and What Comes Next. (New York: Houghton Mifflin Co., 2006), 169.

[7] Ibid., 197.

[8] M-Theory is simply a more generalized version of String Theory

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Philosophical Arguments that the Universe had a Beginning

This is my last blog dealing with the origin of the universe as an argument for the existence of God. I’ll examine the issue of whether new physics might be discovered to enable the universe to be past eternal. I’ll offer a couple of philosophical arguments against the possibility of an eternal past. If these arguments succeed we can be confident that no scientific discoveries could ever show that the universe has existed forever. Indeed if these arguments are sound, the scientific evidence I’ve offered so far would become superfluous.

If the universe has existed forever, this would entail an actually infinite number of past events. I use the term “actually infinite” to distinguish it from a potential infinite quantity. No one doubts that the number of future events can grow without limit but this is merely a potential infinite. Any finite time in the future there would still have been a finite number of events since the current time so the infinity is just potential – it represents an unattainable limit as this article by George Ellis, a prominent cosmologist, indicates.

Is it possible for actually infinite numbers of entities to be realized in the actual world?

One of the greatest mathematicians of all-time, David Hilbert, certainly didn’t think so: “the infinite is nowhere to be found in reality. It neither exists in nature nor provides a legitimate basis for rational thought.“ Georg Cantor established a mathematically rigorous way of dealing with the concept of infinity that is very useful for mathematical and scientific calculations. Although Hilbert defended Cantor’s work, he argued that infinities couldn’t exist in the actual world or they would lead to absurdities.

Some readers may be thinking that if it is mathematically possible it has to be physically possible. But not everything used in mathematics necessarily implies a direct correspondence with physical ontology (nature of being). Infinitesimals are mathematically feasible and highly useful in calculus, but modern physics holds that everything is quantized. Mathematical consistency and coherence doesn’t necessarily imply physical realization – there are abstract mathematical systems that can be constructed that are coherent but not all of them are necessarily realized anywhere in physics. In computer science we often choose between multiple mathematically equivalent but quite different ways of computing things – they can’t all correspond to physical ontology because they entail fundamentally different ways of modeling reality. Infinities that show up in physics equations are considered problematic unless and until some type of renormalization can be performed.

So if we can show that absurdities result if actual infinites exist, then we have good reasons for rejecting the possibility of an actually infinite number of past events – even if it is mathematically feasible. Here is how philosopher Peter S Williams makes this argument to a lay audience:

Suppose I ask you to loan me a certain book, but you say: ‘I don’t have it right now, but I’ll ask my friend to lend me his copy and then I’ll lend it to you.’

  • Suppose your friend says the same thing and so on…
    1. If the process of asking to borrow the book goes on forever, I’ll never get the book
    2. If I get the book, the process that led to me getting it can’t have gone on forever

Somewhere down the line of requests to borrow the book, someone had the book without having to borrow it. It’s easy to see how this analogy applies to the Kalam – if the arrival of the current event/book required infinitely many prior events, it would have never arrived. You cannot traverse an actual infinity. If the current event/book did arrive, the process that led to it couldn’t have gone on forever.

Another example of the physical impossibility of an actually infinite number of items is the following. Suppose that there is one particle of some type for every positive whole number (integer) – we can think of these as comprising a mathematical set in which we’ve numbered the particles. The number of particles is aleph null and represents a so-called countable infinity. Suppose this type of particle is not stable and thus half of the particles decay in some time interval. One could think of the number of particles in this set as now consisting of the even integers. But one can also reach a contradictory answer that the number of particles is the same as the original by proving mathematically that the number of even, positive integers is the same as the number of positive integers.

This mathematical proof is quite simply done by showing a one-to-one correspondence between the elements in the set. For every integer in the original set, there is one integer in the set of even integers (2,4,6, …) obtained by just doubling the original value. Thus, the number of particles in each set is mathematically identical even though half of the original particles underwent decay. After we wait another half-life, half of the remaining particles have now decayed so the set would consist of particles (4,8,12, …). However it can also be mathematically proven that the number of positive integers that are multiples of 4 is identical to the number of positive integers. Have the number of particles been reduced or not? We reach contradictory results – no matter how many half-lifes we wait, the number of particles is the unchanged and has been reduced as per the usual physics equation. Thus, dealing with the actually infinite in reality would violate the laws of physics.

Philosopher Alexander Pruss offers at 6 arguments in support of premise 2 of the Kalam – that there couldn’t have been an infinite number of past events. Although he thinks actual infinities might be possible in general, he doesn’t think an infinite causal chain is possible. “This strengthens the Kalaam argument by showing that the premises can be weakened: the Kalaam argument only needs the kind of causal anti-infinitism that I now cautiously accept.”

Objection: But doesn’t Christianity require that God has lived through an infinite number of events?

There has never been a time at which God has not existed. However, if time is a physical entity that began to exist, it seems to have been something brought about by a cause outside of time. The classic theistic understanding is that God is an eternal being that exists outside of time. There is an interesting passage in the New Testament, Jude 24, that speaks of God having dominion and glory before time began. See also Titus 1:2 for another Biblical reference consistent with the understanding from modern physics that time had a beginning. As evidence of God being able to see into the future one can study Biblical prophecies of the future state of cities such as Memphis, Thebes, Babylon, Ninevah, Ashkelon and peoples such as the Philistines, Edomites, and Jews. (See this link to explore this evidence for divine inspiration of texts known to be written before the fulfillment)

It may be hard for us to grasp something that exists outside of time since we are constrained in this realm. Many scientists, however, do posit the existence of other space-time dimensions and explain how we would be unaware of these – e.g. see the book Flatland, which Hawking and Sagan point to an illustration of the possibility of unseen dimensions. Perhaps God exists in another realm or dimension of time or perhaps William Lane Craig is right in theorizing that God existed timelessly before creation and stepped into time when He created time.

Final Comments on the Implications of the Kalam

The conclusion of the Kalam is pretty modest. It doesn’t establish the existence of a particular god etc. Deism rather than theism could still be true if this is all we had to go on. The Kalam, however, is a strong refutation of naturalism – the view that nature is all there is. Most atheists hold to naturalism and if they admit that it’s false they’ve undermined the most significant traditional arguments for atheism.

A transcendent cause to the Universe possesses some properties of God such as being beyond space and time and being immaterial. It’s pretty hard to deny this as atheist scientist Lewis Wolpert discovered in his debate with William Lane Craig. Wolpert admited that the universe had a beginning saying “well we know that, nobody disputes that.” The ease with which he is willing to admit this should bother you if you’re a skeptic as it is yet another testimony to how this argument depends only upon mainstream, widely accepted science. Wolpert’s assertion that it might have been a very special computer fails miserably as one can see here.

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Much Ado About Nothing

In my blog series on scientific evidence for God, I’ve initially focused on the origin of the universe. I defended the Kalam cosmological argument and argued that since currently known physics shows that the Universe had to have a beginning there must be a transcendent cause possessing some attributes of the classical understanding of God (as a spaceless, timeless, and immaterial being) Thus, the Kalam provides good reasons for believing in theism over atheism – I claim it provides epistemic support rather than constituting a deductive proof because we cannot prove the premises beyond the shadow of a doubt.

I appreciate the comments and interaction thus far! John raised another good question recently about whether the quantum vacuum could have appeared from nothing and I responded briefly:

Even if our entire universe fluctuated into existence from the quantum vacuum this would not be a defeater for the Kalam unless one could also show that the quantum vacuum is eternal. If spacetime had a beginning, as currently known physics[1] indicates, then so did the quantum vacuum and thus a transcendent spaceless, timeless cause of the Universe would still be required. But if the quantum vacuum itself could emerge from absolutely nothing then the materialist/naturalist would have a path to creating a universe without a god.

I promised to blog in response to this important question, so here it is.

Is it possible for the quantum vacuum to emerge from absolutely nothing?

By “nothing” I mean simply the usual English definition of “not anything.” The concept of “nothing” defined in this way has no properties and thus no potentiality to bring about something. A widely accepted tenet of philosophy is that “out of nothing, nothing comes.” The quantum vacuum is certainly not nothing because it has properties and ones that can be modelled quite accurately using mathematical equations! The quantum vacuum is best thought of as the lowest energy state in spacetime. Sir Martin Rees, Astronomer Royal of the UK, explains:

Cosmologists sometimes claim that the universe can arise ‘from nothing’. But they should watch their language, especially when addressing philosophers. We’ve realised ever since Einstein that empty space can have a structure such that it can be warped and distorted. Even if shrunk down to a ‘point’, it is latent with particles and forces – still a far richer construct than the philosopher’s ‘nothing’. Theorists may, some day, be able to write down fundamental equations governing physical reality. But physics can never explain what ‘breathes fire’ into the equations, and actualised them into a real cosmos. The fundamental question of ‘Why is there something rather than nothing?’ remains the province of philosophers.

Too bad Lawrence Krauss didn’t heed Rees’s warning. Krauss wrote a book entitled “A Universe from Nothing: Why There Is Something Rather than Nothing.” The book’s subtitle references this great question of philosophy about which contemporary philosopher Derek Parfit exclaims: “no question is more sublime than why there is a Universe: why there is anything rather than nothing?”

In the comments section of a critical blog written by ardent atheist Jerry Coyne, Krauss ironically admits his book doesn’t live up to its subtitle “I may not be focusing on the classical question that has bother philosophers, but I don’t think I ever claim to.” But Lawrence, you made that the subtitle of your book! So when pressed even Krauss seems to be backing away some from claiming that the Universe can be created from a state of nothingness prior to the existence of a quantum vacuum. Other times he does seem to be claiming this but even Coyne criticizes him for “a bait-and-switch.” Krauss is equivocating between different definitions of nothing in his argumentation.

Whatever Krauss might be claiming there is no basis for claiming that the quantum vacuum can originate from a state of absolutely nothing. There is no physics of non-being. No scientific experiment has ever been performed in the absence of space and time and thus there is no scientific basis for extrapolating from ‘not anything’ to the physical world.

For a more detailed critique of Krauss by those much more knowledgeable and articulate than myself please read this blog by cosmologist Luke Barnes – here is an excerpt:

Krauss repeatedly talked about universes coming out of nothing, particles coming out of nothing, different types of nothing, nothing being unstable. This is nonsense. The word nothing is often used loosely – I have nothing in my hand, there’s nothing in the fridge etc. But the proper definition of nothing is “not anything”. Nothing is not a type of something, not a kind of thing. It is the absence of anything.

Barnes also has a follow-on blog that is quite helpful where he states:

if something can some out of nothing, then anything and everything can and should come out of nothing at all times and places. This, then, is the empirical evidence we would need in order to believe that the universe could come out of nothing.

I also highly recommend this scathing review of Krauss’ book by philosopher/physicist David Albert that appeared in the NY Times. Here is an excerpt from Albert:

[Physics has] nothing whatsoever to say on the subject of where those [quantum] fields came from, or of why the world should have consisted of the particular kinds of fields it does, or of why it should have consisted of fields at all, or of why there should have been a world in the first place. Period. Case closed. End of story.

But don’t Christians also claim in a creation from nothing?

Note that when theists speak of “creation ex-nihilo” they are referring to creation out of nothing physical. The Christian view is that God is an eternally existing necessary being and so there was something causally before the Universe began (but not temporally since there was no time!)

Note that there are also independent reasons for thinking that a necessary being such as God must exist – for example in the Leibnizian cosmological argument. I chose not to get into that argument because my series of blogs focuses on science and that is a philosophical argument that doesn’t even depend on the universe having to have a beginning. So in the Christian view, God created the Universe out of nothing physical. While that sounds very mysterious to us, science itself has shown us that all of space, time, matter and energy came into being in the finite past. There is nothing physical or natural left to appeal to as a causal explanation. Thus, by deduction we’re left with a supernatural cause – a cause beyond nature.

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[1] By “currently known physics,” I mean the well understood physics of General Relativity and physics associated with semi-classical spacetime. Because no one knows the correct version of quantum gravity, it is possible that new details concerning quantum physics could permit a past eternal universe. Aron Wall has published some good arguments for why one should not expect any new discoveries in quantum physics to overturn the current understanding that the universe had a beginning. Vilenkin has also argued along these lines as well.

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Objection to Premise 1 of the Kalam: Doesn’t Quantum Mechanics Violate the Causal Principle?

It depends on what you mean by causality. A philosophically-informed physicist would say Quantum Mechanics (QM) doesn’t do away with causality:

“In fact, QFT[Quantum Field Theory] is constructed in such a way to explicitly preserve causality. Any QFT textbook devotes 10 pages of chapter 1 to explain why the square root of the Klein gordon equation does not make a good wave equation for a QFT – it cannot preserve causality.”

In physics, we speak of things happening based on mathematical laws. For example, two electrons are repulsed by the electromagnetic force and we can compute their path of motion. There seems to be a clear causal connection because the math is fully deterministic. In QM, the only difference is that the math is probabilistic rather than exact. No one is even sure that QM is indeterministic – Bohm’s interpretation might be right. Even if QM is non-deterministic, is it appropriate to say that things are happening without causes? We can use the Schrödinger/Dirac equation to make quite accurate probabilistic computations concerning the evolution of a system. We may not know when a particular radioactive atom will decay but we can use statistically large sets of atoms to accurately perform radiometric dating.

To be sure, there is a lot of controversy over how to interpret causation in QM (e.g., does the observer play a role?) but I don’t think QM really does away with the causal principle in the sense relied upon by the Kalam. The Kalam relies only on there being underlying reasons for things coming into being. If something happens in a manner that can be probabilistically predicted (as is always the case in QM), then it’s not a case of something being created without a cause from absolutely nothing. Things originating without causes could not be predicted even probabilistically!

Here is philosopher/Physicist David Albert on how Quantum Mechanics doesn’t explain the origin of the Universe from absolutely nothing: “The fact that some arrangements of fields happen to correspond to the existence of particles and some don’t is not a whit more mysterious than the fact that some of the possible arrangements of my fingers happen to correspond to the existence of a fist and some don’t. And the fact that particles can pop in and out of existence, over time, as those fields rearrange themselves, is not a whit more mysterious than the fact that fists can pop in and out of existence, over time, as my fingers rearrange themselves. And none of these poppings — if you look at them aright — amount to anything even remotely in the neighborhood of a creation from nothing.”

The Borde-Vilenkin-Guth theorem that I referenced in the previous blog indicates that spacetime cannot be extended into the infinite past. QM operates within spacetime so if spacetime is not eternal it is unreasonable to claim that quantum processes have been eternally in operation. Some physicists do speak of highly speculative theories of creating a universe out of the quantum vacuum but the quantum vacuum is not nothing – it’s just the lowest energy state of spacetime. It’s weird to think about spacetime not existing but such is the implication of BVG and the earlier Hawking-Penrose singularity theorems. This Scientific American article might be helpful in explaining how the Big Bang is not just describing expansion into “some imagined preexisting void.” The Big Bang is not dealing with expansion into preexisting space but the expansion of space.

For more details on the problems when some scientists speak about the Universe being created from absolutely nothing I highly recommend this blog by cosmologist Luke Barnes.

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