Entropy, the Big Bang and fine tuning for the mathematically inclined

Faith & Science Conversation
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Just thought I’d post this for anyone who’s particularly mathematically minded. It’s a video on the YouTube channel Physics Explained that deals with the subject of entropy and why time only appears to go in one direction. It also covers the question of fine tuning towards the end.

I thought it particularly interesting because my big frustration with the fine tuning argument is that so often in apologetics, it’s presented in a very vague and woolly fashion, telling us that if certain parameters had varied by only one part in x billion trillion squazillion handwaveillion then life could not have arisen, because reasons. Sometimes I even wonder if they’re just pulling the figures out of thin air. But this one is different: it explains the concept of entropy in terms of microstates and macrostates, how we calculate the probability that a certain microstate could come about (e.g. all the air molecules in a box coming together in one corner at random), and then applies the same principles to what we know about the very early universe from observations such as the cosmic microwave background. It uses this to calculate the entropy of the observable universe just after the Big Bang, and the entropy of the observable universe today, and it uses this to derive figure for the likelihood that the universe could have arisen by chance with the amount of smoothness that we observe as just one part in 10^{10^{123}}.

Whatever you make of fine tuning, I thought it was nice to see it given a rigorous mathematical treatment with some definitive figures and data behind it for once.

The Physics Explained channel has a lot of other videos explaining physics concepts from a similarly rigorous mathematical perspective. It’s nice for a refresher of all the stuff I learned at university and have since forgotten.

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Extremely interesting. This also reinforces an idea I’ve had for a while: that the perceived need many people feel to affirm the existence of a multiverse arises precisely from the recognition that the likelihood of our universe turning out the way it has by mere chance is, on its own, essentially negligible.

But if we instead posit an unprovable multiverse in which billions upon trillions of universes exist or have existed—if I’m not mistaken there are two versions of this rather convenient fairy tale: one in which infinitely many universes, each with different constants and laws, exist simultaneously, and another in which there is an infinite sequence of universes, each with different constants and laws—then poof, the problem disappears. We can simply claim that this universe is the way it is because the dice have been rolled billions of trillions of times until this particular outcome finally and unavoidably appeared. Cosmic neodarwinism in a nutshell.

A nice fairy tale, I’ll grant them that—but a fairy tale nonetheless.

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Interesting, James. I have heard those arguments. It might just be “Me” –and I hated math in school long ago — but the statistics and the notion of probability in the case of an unguided universe – these all make sense to me. There are many things in the human body (forget the universe!) that keep us going. I was being tested for something else when the phys therapist had me do a peculiar exercise where you stand still for 60 seconds with your eyes closed. Do the exercise three times – opening your eyes in between sets. When I was done, she said that when your eyes are open, the body has many cues by which to balance itself. But when your eyes are closed….the only thing balancing you is your inner ear (or is it the middle?). I thought about the exreme likelihood that a non-thinking completely random universe would have devised something like the balancing mechanisms in the [inner?] ear –just by chance just randomly and all the while keeping that galaxy beyond Andromeda from falling down a black hole. Too many coicidences for no thought to have been involved. I don’t know if those people to whom you refer are “just pulling the figures out of thin air” – but why not ask them? Most are pulling the numbers out of a book they just read, which is also good. That is why we read books. But a thoughtless random universe likely would never have come up with the aardvark on its own [for one example]. OK… off my soapbox.

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The multiverse is just, essentialy, materialism of the gaps.

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No. It’s a possible outcome of QM and cosmology. There may be additional metaphysical inplications at play but let’s not dismiss the actual investigations and theory building quite so blithely. That status of whether this is a single, fine tuned universe vs. part of a multiverse vs anything else not yet considered is “We don’t know”.

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Yeah, I was just mentioning the reason why it’s so liked by many people. And the reason is that it offers a materialist explanation for fine tuning.

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And why people may prefer the single-event, fine tuning option for other metaphysical & religious preferences.

What I find amusing or tiring, depending on the day, is that neither option demonstrates or precludes the existence of God.

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That’s true—I’m not denying that. But it’s still striking how quickly these unprovable theories emerged as soon as ideas like the Big Bang—which suggests that the universe had a beginning—and fine-tuning came into prominence.

Well, this is technically and substantially true. However, the hypothetical discovery that we are living in a universe among billions or trillions of others—each with different laws and constants—would admittedly further reduce the visibility of God (as the constants and laws we observe in our universe would simply be the result of a process analogous to a dice being rolled trillions upon trillions of times. ) It would push belief in God more into the realm of an ‘absurd leap of faith,’ seemingly disconnected from the real world—which is precisely what some people want.

This is also why many were resistant to the so-called Third Quest for the historical Jesus: it showed that the New Testament was written much closer to the events than previously thought, that the Pauline creed is extremely ancient, and that the apostles genuinely believed they had seen the risen Jesus. Of course, historians operate under methodological naturalism, which means they cannot conclude that the resurrection actually occurred; they can only say, as they do, that the evidence strongly suggests the apostles sincerely believed it, and that this belief explains the rapid rise of Christianity. All of this stands in contrast to the long-standing narrative that the Gospels were no more historically reliable than The Silmarillion, that they were written centuries after the events, and that the resurrection was a later invention.

Admittedly, this earlier view (the one that basically negated any historical legitimacy of the NT) did not lead believers to abandon their faith. But from the perspective of some atheists, the goal is not necessarily to force disbelief, but rather to confine religious belief to the realm of superstition, detached from reality. This helps explain why the Third Quest has not been well received by many, and why some continue to repeat positions on the subject that may have been defensible a century ago but are far less so today. A similar dynamic can be observed with the Big Bang and fine-tuning: the multiverse hypothesis is often welcomed because it offers a materialist explanation for both the origin of the universe and the apparent fine-tuning of its constants.

And yet, the hard problem of consciousness remains. It continues to suggest that people may not be entirely mistaken in thinking that they are more than mere worthless beasts. Still, one can easily imagine how appealing it would be, for some, to demonstrate conclusively that consciousness is entirely reducible to matter.

So yes—you are both technically and substantially correct. But we should not overlook a rather clear point: the hypothetical discovery of a multiverse would almost certainly be used to push God further into obscurity and hiddenness.

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God does what God wills.

Ironically, one purpose of this board is to help YEC Christians come to grips with an ancient Earth, deep time and biological evolution. All scientific ideas that some YECs and OECs choose to deny with the many of the same arguments.

As the Bokononists from Kurt Vonnegut’s Cat’s Cradle book would say:

Tiger got to hunt,

Bird got to fly;

Man got to sit and wonder, “Why, why, why?”

Tiger got to sleep,

Bird got to land;

Man got to tell himself he understand.

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Love God and fart around, the gospel according to Vonnegut

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I fully accept an old Earth and the theory of evolution; however, I cannot deny that, for many people, these have been stumbling blocks to faith. Whether this is justified or not is a separate question, but it remains the case that such scientific discoveries have posed genuine difficulties for many. To deny this would be to ignore an observable reality.

I also believe that there would still be many theists even if the existence of trillions of universes—each governed by entirely different laws and constants—were conclusively established, and even if it were demonstrated that consciousness arises entirely from natural, material processes.

Nevertheless, one should be candid: would not such a scenario render belief in God significantly more difficult than it is at present?

The multiverse hypothesis may ultimately prove to be true or false. However, the eagerness with which it is sometimes advanced appears, at least in part, to be motivated by a desire to exclude God, or at least to deny the rational legitimacy of belief in God. In many post-Enlightenment Western societies—particularly in Europe—religious belief is often tolerated, yet attempts to defend it on rational grounds are met with considerably less openness. From a theological perspective, this cultural trajectory may be interpreted as consistent with the ‘great apostasy’ described by the Apostle Paul. And I believe we are into it.

It will likely take many decades—perhaps even another century or two*—before the final unleashing of evil, namely the “man of lawlessness” that Saint Paul foretold, also known as the Beast in the Book of Revelation. Nevertheless, I believe we are already in the initial stages of this process.

*At least, I hope so, for I would not wish to be alive when these events come to pass.