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.

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Regarding that last bit about fine tuning, this is the first time I’ve ever seen anyone showing that math for such a thing - pretty much all the others have been making stuff up. This remains considerably different from those other claims in that is has a particular interpretation; the tail probability of the an initial BB state IF that state is random.

A few points;

  1. It’s not clear that universes should be able to pop into existence in any other state. Given that entropy of a universe can only increase, ANY initial state should be fantastically low compared to what follows.
  2. this says nothing about the probability of events following the BB, which is the usual playground for bad fine tuning arguments.
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Indeed the probability is impossibly low for our universe to exist without a creator, and yet a materialistic view would claim we are one of trillions of universes, and that would therefore suggest how our universe could exist without a creator God. HOWEVER, based on quantum mechanics these wave forms of possibilities do not collapse into reality unless they are consciously observed. But how can a God know which one to observe you may ask? The answer to that is that the uncertainty principle does not apply to a non-temporal God who exists in all times past and present, and sees all possibilities and chooses the one that created our universe. This is the ONLY explanation to the reality we observe at least to my mind. Anyone have another explanation? If so I would be interested in hearing it.

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Last evening I listened to a lecture by Richard Feynman about how water behaves contrary to expectation in many ways and is very unique in this, to the point that if water were any different on any one of those behaviors there wouldn’t be life. It struck me as another sort of fine-tuning.

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It is a good mathematical presentation but it is oversimplified. There is so much that can be said that I find it difficult to present in an ordered fashion. I’ll present a set of points…

  1. From an energetic standpoint, every process results in some of the energy available to do work being converted into energy that is unavailable to do work. Matter/energy is conserved but the useful energy diminishes. This is due to local entropy changes, not to the formation of black holes. The arrow of time is clear from examining any process in detail. It is the reason why perpetual motion machines are impossible.
  2. The expansion of the universe is an expansion in space-time and at the big bang (the moment of creation) there was no space-time and the energy was infinite. That is what we call a singularity. By the way, It is not an explosion (a big bang) because an explosion is matter moving through space. It is matter and energy moving in space.
  3. Matter-energy and space-time came to be from nothing. Yes, there are theoretical speculations but none have experimental support. They are fundamentally science fiction.
  4. Calculating the entropy of the universe as described in the video ignores the expansion of space-time.
  5. The uniformity of the background radiation can be explained by energy equilibrating and does not imply that at time zero the energy was at equilibrium.
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I agree. The properties of water are especially important but so are those of many elements. Carbon’s ability to generate so many molecules is unique.
Marco

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That’s why they seized the opportunity when the theory of the multiverse emerged—it offered them a way to push God out of the picture. But none of this is new. The Bible already tells us that the whole world lies under the power of the Devil (1 John 5:19). Especially in the West, this seems increasingly evident—just consider cases like Epstein and the many highly influential people connected to it, in pedophilia and demon worshipping. *

Think about why religion and spirituality have been dismissed as superstition, while materialism is presented as the (never proven) scientific view. This world is ruled by the principalities, the powers, and the rulers that Saint Paul speaks of in Ephesians 6:12

No matter how backwards and absurd this may sound to our post-enlightenment ears and brains.

*Many dismiss the idea of demon worship in this context (the Epstein case) as a mere conspiracy theory, yet they still grant authority to the Bible, which states plainly that the entire world lies under the control of the Devil. It is as though they ignore the very obvious truth that many of those who govern the world have submitted themselves to the principalities, powers, and evil spirits described in the Letter to the Ephesians.

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Terrific youtube on the physics of it all…thanks James.
I’m trying to reconcile the concept of macro and micro states regarding a mathematical explanation for the “impossibility” of getting to where we are, with the Anthropic Principle. The AP asserts that we observe the universe to be as it is, and compatible with life, because if it weren’t, we would not be here to observe it. In other words, it did not have to be ‘fine-tuned’ for us, because we can only find ourselves in a universe where conditions allow us to exist.

We may indeed live in an impossibly unlikely state, but given that we DO exist, it is not surprising that we observe the very things that we are now trying to define. To repeat an old analogy about a firing squad, if 100 experts aim at you, fire, and yet you survive, you might assume that “someone intended for you to live”. But only a survivor can wonder about that improbability.

How do we, or should we, make the two concepts compatible?

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Only a survivor can truly reflect on such an improbability, that’s true. Yet you did survive (in the aforementioned scenario), and that is a fact.

The question is: what are the odds of one hundred trained men firing at you and all of them missing? Astronomically low. So low, in fact, that they are almost nonexistent. In such a scenario, it would seem irrational to attribute the outcome to mere chance. One would have to assume either that they missed on purpose or that some external force intervened to make the impossible… possible (“nothing is impossible with God,” as the Bible states. I understand that some people, even among theists, believe that God never intervenes in reality and that He cannot bend His own rules, as if He is constrained by the very rules He created, but that is another matter).

However, here lies the key point: if we posit that the same scenario is occurring (or has occurred) trillions upon trillions of times, each with wildly different outcomes, then even an event with “impossibly low” odds—such as the one you described—becomes not only probable but inevitable. No matter how unlikely an event may be, or how astronomically low the odds of it occurring are, if it is both logically and physically possible, and the “dice” are blindly rolled enough times, it is guaranteed to happen without the need of any “superior intelligence”.

Which is why the multiverse hypothesis is so appealing to the materialists.

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Absolutely not. Just as we do NOT have to assume the impossibility of our current state of existence (we are here, after all), we do not for the firing squad. Both scenarios are the same: improbable to the point of being impossible, yet we see one in reality (the universe as it is today) and stipulate the other as a thought experiment. One cannot reject the thought experiment just because it reaches a conclusion one does not like.