Thursday, February 12, 2015

Quantum Eternity and Young Earth Creationists

Yesterday's post about scientific evidence that something material having always existed got some interesting reactions off site.

Eventually I came across this Q&A by William Lane Craig to attempt to answer what Sean Carroll called the Quantum Eternity Theorem.

Here's the first part that truly struck me:

"Saying that the time variable t runs from −∞ to +∞ just implies that quantum time evolution is information-preserving: “given the current quantum state, we can reliably reconstruct the past just as well as the future.” In other words, we can extrapolate from the present indefinitely into the past or future. This allows us to describe a moment prior to a given moment if there is such a moment; but in order to know whether there is such a moment we must look to empirical evidence. "
- William Lane Craig, Reasonable Faith Q&A

This was very similar to an argument I got elsewhere that things like quantum mechanics don't really address whether or not material things were created or not, but rather describe "already existing systems".

This is part and parcel of how apologists will try to evade the kinds of points I brought up saying how we have some evidence that "something material has always existed".  It's effectively a way to insist that there is a metaphysical question that can't in fact be answered by any kind of scientific evidence.

In order to respond to this, it's very important to see exactly what the theist is claiming here.  As charitably as I can interpret them, it goes like this:

The material world is described by laws (or regularities) that make it look like it has always been there, if we assume those laws have always applied.  However, theism does not assume that those laws have always applied. Effectively there is no logical contradiction to believe that god created a universe that looks like it can't be created or destroyed once it exists.

So what are we to think of this?


I am actually inclined to very much agree that there is absolutely no logical contradiction in saying that at one point there was just god, and then that god created a universe that "from the inside" appears to operate with regularities that entail it should have always existed.

I tried my best to allude to this in my addendum to yesterdays post, specifically that there is certainly conceptual space for theism to accommodate literally any view we would get from science.

Is This a Problem?

Some atheists might be inclined to make a point out of that, claiming theism is thus unfalsifiable and should be rejected.  I may have been like that a few years ago, but now I know a bit better because naturalism does the same thing.

Specifically, naturalism itself has no problems accomodating an infinitely existing material universe, a material universe that has a beginning, or a material universe where time is not fundamental and so the material just exists.

So it's not really a problem that theism could accommodate any view we get from science.  Because theism, like naturalism, is a framework that tries to explain the fundamental nature of reality.

It's not all sunshine and roses however since this does present a problem for religious apologists like Craig who want to use natural theology to convince people that a god exists.  That's the downside of "retreating to pure metaphysics", any empirical investigation doesn't really do anything to help you make your case.

But then doesn't this pose an equal problem for what I wrote yesterday?  Since my naturalism can also accommodate whatever eventual scenario science gives us?  It sure seems like it, but I think I've got a pretty solid out.

Switching from Offense to Defense



The problem for the theist is that they say the laws of nature apply up to a point, roughly 13.8 billion years ago, at which point they no longer apply.  In saying the laws of nature themselves had to be created seems to be a bit of an arbitrary jump in the context of the cosmological argument.  That's because we're watching the theist jump from being on the offensive in using a cosmological argument that appeals to scientific evidence to playing defense when that evidence undermines the conclusion they want.

Certainly a theist could try to just argue that the laws must be created as it's own point to be addressed on it's own, but we're starting this in the context of the cosmological argument.

The naturalist is at least consistent in that we assume these laws of nature always apply, with no stopping point.  We'd also clarify that the "laws of nature" are merely descriptors of the regularities we see in nature, and that those regularities are simply what material "does".  The nature of nature, so to speak.


Help from an unlikely place

The theistic move to get to their metaphysical creation is not unlike another kind of theistic solution to problems that plague a far more crude form of theism: Young Earth Creationists.

When we point to the speed of light being a constant and the fact that we have starlight from billions of light-years away, the YEC actually has a response.  It's Ken Ham's old gem of "historical science", basically saying the idea that the universe is 13.8 billion years old instead of only a few thousand years is given the assumption that the laws of nature are consistent and have always applied.

What they argue for is that the universe was created 6,000 - 10,000 years ago with the appearance of being 13.8 billion years old, given those assumptions we make about how we observe the universe operating now.

Now creationists like Craig and other modern apologists who want to get away from the absurdities that YEC entails deny that belief in Christianity requires them to make such a move.  But just what is it on their view that makes the YEC move invalid?  Eventually, these more sophisticated creationists must make the exact same jump: that the laws of nature we see governing reality now don't apply always apply.  The only difference is that these creationists pick 13.8 billion years ago as the stopping point, rather than only 6,000.

The out for me as a naturalist is that I can hold true to saying that thees laws apply universally rather than picking an arbitrary stopping point.

But aren't they appealing to empirical evidence?

A good part of this post is addressing objections I've come across besides the article I'm quoting Craig from.  I think eventually he's forced into the issue I laid out above, but he at least is making a show of appealing to empirical evidence.  That's where I want to turn now.

Much like he did in the debate, Craig appeals to the idea of a "thermodynamic beginning", basically the fact that our universe had a low entropy condition in the past.  That's a very important question in physics to which we have only speculative answers, but it doesn't do the work Craig tries to get out of it here.

Craig points to the Carroll-Chen model that has the low entropy condition at the center of a universe which has two arrows of time, each pointing in opposite directions coming out of that point.  Much like in the debate he wants to focus on what is admittedly a more speculative model and not one that is nearly as well defined like the Aguirre-Gratton model.  The point being that the Carroll-Chen model isn't the only game in town to address these issues.

In any case, Carroll's reply from the debate holds true: it is misleading to say that such models have a thermodynamic beginning.  There is simply a point in the model of the universe in which the entropy is at its lowest, the model is still entirely self contained.

Craig seems to recognize this, and so wants to attack the assumptions of the model which is premised on the idea of the total energy of the universe being non-zero:

"For example, maybe the Hamiltonian operator H^ does have a zero value. The physicists I’ve consulted tell me that the evidence is fairly weak that there is a time-independent Hamiltonian with non-zero energies and that most quantum cosmologists think it is zero or undefined. In his blog Carroll notes that
"This kind of scenario is exactly what quantum cosmologists like James Hartle, Stephen Hawking, Alex Vilenkin, Andrei Linde and others have in mind when they are talking about the ‘creation of the universe from nothing.’ In this kind of picture, there is literally a moment in the history of the universe prior to which there weren’t any other moments. There is a boundary of time (presumably at the Big Bang), prior to which there was . . . nothing. No stuff, not even a quantum wave function; there was no prior thing, because there is no sensible notion of ‘prior.’"

Here we confront the evidence of big bang cosmogeny for the past finitude of the universe to which I appealed in the debate. As I argued, postulating a quantum gravity era from which our classical spacetime “emerged” does not subvert but actually supports the conclusion that the universe began to exist."
- William Lane Craig, Reasonable Faith Q&A 

The problem here is that if the Hamiltonian operator does have a zero value, then time itself isn't fundamental.  The quantum description of reality doesn't have a time descriptor. Let that sink in, time itself in that scenario is not real, it's emergent.  This is not some atheistic view to avoid inferring a creator, even Evangelical Christian physicists like Don Page are sympathetic to this view.

The entire thing becomes a game of how you look at the situation: we say there is nothing beyond the boundary of space-time because there is no sensible notion of "prior".  

Craig tries to flip this around by saying this somehow supports creation - except in this scenario the quantum description of reality is still a material something.  It's not "nothing" in the philosophical sense of the term, and it is still governed by the laws of quantum mechanics.  In fact, what Carroll is referring to in the quote is just a quantum mechanical description of a stand-alone finite block universe that would exist on the B-Theory of time.

In order to say that a god created this quantum "stuff" which in turn is just a quantum mechanical description of a what we classically called a 4D space-time universe, Craig has to  re-impose another concept of time! Except it can't be related in any way to the time we experience, we've already established that time doesn't exist in this quantum description of material reality because the Hamiltonian operator is zero.   This is it's own metaphysical problem I've documented elsewhere in my response to Craig on Kalam.


To add insult to injury Craig further claims:
"Moreover, such a scenario does not imply a tenseless, static, so-called B-theory of time, since the Hilbert space in which spacetime is described is not a real space but merely a mathematical space."
- William Lane Craig, Reasonable Faith Q&A 

This is just an assertion that the Hilbert space is not representative of real space, it's an allusion to the conclusion he draws in his arguments against space-time realism.  This is its own view in philosophy of science, one that has much controversy around it that's mostly unrelated to our issues at hand.  But even if one doesn't hold to space-time realism that doesn't mean that suddenly the B-Theory is false and that we must adopt the A-Theory.  Craig still faces all the problems appealing to scientific evidence brings up for the A-Theory that I've documented here.

Conclusion

There was a lot said here, but in the end we still get to the same conclusion:

Either we hold to the laws of nature applying universally, or we say that they must have a stopping point in which they do not apply. 

Appealing to the empirical evidence doesn't get around that problem.  What Craig ends up doing at the end there is simply deny that the naturalist can stop at the point of a boundary of a space-time block-universe.  We have good reasons to think that, namely that once we do hit this quantum description of space-time, we stop being able to describe it with respect to time. That doesn't mean we can't describe its behavior at all, or that it's nothing, or that we can infer that it must have had a cause.

While a theist may be able to play the "well you can't prove it wasn't created and my conception is perfectly coherent" defense - that doesn't change the fact that they can't argue it must have either.

The entire enterprise ends in a stalemate, and so the cosmological argument would fail to establish its conclusion.

But if we are going to say that there is a material reality, and that this material operates in a certain way, what naturalists mean by saying the "laws of nature", then the universe can very well be self contained based on what we find.

1 comment:

  1. "Specifically, naturalism itself has no problems accomodating an infinitely existing material universe, a material universe that has a beginning, or a material universe where time is not fundamental and so the material just exists."
    In reference to this passage, based on what i have read on this page, you are not opposed to a finite regression. Finite regression as in the sense, if you go back from the chicken to the egg to the earth to the universe, ultimately there is something eternal at the end (or rather the beginning). However you assume that what is eternal must be material, an assumption directly contrasting to the views of theists as myself. God is not limited to what is material, though he can exist as such. It is the belief of theists that god exists and existed in such a state prior to the creation of our universe/reality. Another point you make, if I understand correctly, is that for god to invent time, he must exist in another time because in order to create whatever he is creating it cannot have existed prior. This is a view based on our reality and the way we perceive space and time. If god exists outside of time, or rather is not limited to existing in time because he is not material, he is capable of "creating" time in the sense of our perception without existing in time.

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