How the Universe Got Its Spots, Part 1

I heard a story on The Moth podcast by Janna Levin. (I don't link directly to it, because it will be gone from their archives, soon.) It made me realize that at least one cosmologist shares some of my discomfort with the idea of living in an infinite universe with infinitely many exact copies of myself. Of course, it is possible this is true. We can't prove it one way or another, yet, but Dr. Levin said, mostly as a structural element to her story, that the universe might be finite. I got curious, and was able to check out one of her books from my local library system. How the Universe Got Its Spots is half an introductory course in cosmology--definitely for the layperson (I'd learned most of the stuff in a modern physics class, already)--and half diary. It is liberally sprinkled with Janna's (I can't decide how to refer to her, since the book makes you feel like first name is appropriate, but I've never met her) philosophical musings about what different universes would mean for our existence. I've excerpted a number of passages that speak to my own aesthetic prejudices about the universe.

Before I begin this long series of quotes and comments, I need to make a distinction. When Janna talks about the universe, she is referring, usually, to the contiguous (connected) domain of spacetime that arose from the Big Bang that eventually made us. She is not discussing whatever might be "outside" our universe, or whatever realities might not be connected to our spacetime (at least not in ways we yet understand or observe--there is always that caveat with science). I guess now I'll just start . . .

The universe had a beginning. There was once nothing and now there is something. What sways me even more, if an ultimate theory of everything is found, a theory beyond Einstein's, then gravity and matter and energy are all ultimately different expressions of the same thing. We're all intrinsically of the same substance. The fabric of the universe is just a coherent weave from the same threads that make our bodies. How much more absurd it becomes to believe that the universe, space, and time could possibly be infinite when all of us are finite.  p. 4

In some sense, the Big Bang really was a beginning of our universe from nothing. There were none of the elements that we are used to thinking of as making up our bodies. There weren't even the subatomic particles that quantum mechanics describes. The law of conservation of matter doesn't obviously apply at this singularity in any way we are used to thinking about it. I remember reading a speech where Joseph Smith picks up a ring and uses it to illustrate his point that anything with a beginning must have an end, so creation ex nihilo is an absurdity if we think we are going to live forever. I wholeheartedly agree with Joseph on this. But it looks like we were created (our bodies as we know them) from "stuff" that didn't exist before about 14 billion years ago. We had a beginning, and it looks like we will have an end if our matter is all we are. This would have seemed like a problem to me, in the past, but now it actually offers hope of solving some problems for me. But that's getting ahead of Ms. Levin's story arc.

Don't get me wrong, I don't believe that math and nature respond to democracy. Just because very clever people have rejected the role of the infinite, their collective opinions, however weighty, won't persuade mother nature to alter her ways. Nature is never wrong. Still, I don't believe in the physically infinite.

Where in the hierarchy of infinity would an infinite universe lie? An infinite universe can host an infinite amount of stuff and an infinite number of events. An infinite number of planets. An infinite number of people on those planets. Surely there must be another planet so very nearly like the earth as to be indistinguishable, in fact an infinite number of them, each with a variety of inhabitants, an infinite number of which must be infinitely close to this set of inhabitants. Another you, another me. Or there'd be another you out there with a slightly different life and a different set of siblings, parents, offspring. This is hard to believe. Is it arrogance or logic that makes me believe this is wrong? There's just one me, one you. The universe cannot be infinite.

Of course, my faith in nature and it's laws is deeper than my need for uniqueness. If I truly believed there was no way for the laws of physics to be consistent with a finite universe, I might be swayed. But there are ways, simple ways, for the laws of physics to be consistent with a finite universe. p. 14

There's the first problem fixed. I seem stuck on this idea that for my life to have the kind of meaning I want, I need to be unique, and it looks like that isn't a problem if the universe is finite. Arrogance? Probably of some kind, but maybe physics will prove my arrogance justified. At least my prejudices don't obviously violate physical laws. But being unique only solves problem with the universe I want to give meaning to my life. Janna brings up the second a few pages later:

There is an unresolvable philosophical debate that rears its ugly head on the impossibility of free will in a life dominated by determinism. The distilled and simplified argument goes something like this: if every atom in our bodies merely follows a mechanical trajectory precisely determined by the laws of physics then we have no volition. Our choices are predetermined and we merely play out the inevitable effect of all those earlier causes.

A deterministic universe is like a movie where the end is already recorded. We don't know the ending, so we have the impression that it's unfolding in real time and a sense of spontaneity, but the end is already written, already determined. Maybe nature has restricted our perception in this way to protect us from the completely bleak state of affairs of knowing the ending, but it's an illusion all the same.

People used to try to hijack quantum mechanics and its inherent mystery to cast a cloud around determinism, in the hopes that free will could survive modern physics. But that never worked very well. Since when does random chance equal free will? The only salvation for volition is a soul and faith and you're not allowed to ask me about that. p. 21

You are allowed to ask me about faith and souls, but that's not our topic, here. What's notable to me is that Janna also thinks the debate about free will is unresolvable. I've heard people talk about free will and determinism, and I've corrected a number of misconceptions I've had. I've spent several weeks (or months) browsing and mulling over articles in the Stanford Encyclopedia of Philosophy about compatibilism, incompatibilism, free will, and the like. I've tried (and partly succeeded) to make sense of all of the logical formalisms, and it really looks to me like the only way to ultimately answer the question of free will is to make a few unprovable assumptions and go from there. That isn't to say that I think all possible sets of assumptions are useful or true. Some sets of assumptions clearly contradict observable data, so the possibilities aren't endless. But among the various possible assumptions, one seems to dominate modern philosophy--determinism.

I currently believe in some type of deterministically constrained (probabilistic) randomness, because it seems to me that that is what we live with. Most objects move deterministically according to Newton's laws even down to atomic motions, but some small part of reality (double meaning intended) really is fundamentally random. I don't have any idea where free will comes into play. I've read and listened to accounts of lots of psychology that makes it pretty clear we aren't as free to choose as we typically assume--probably a lot less free than we usually think. I know all this, and accept it at some level. I think we should use this knowledge to improve our lives. But in saying that I hang on to some notion of original agency (I made a choice, and I could have done otherwise--really, not just theoretically). The problem with an infinite universe is, I can't see any way for me to hang on to the sense of agency I want. I'm not sure even faith and a soul can save my agency. Here's the problem--

How can I believe in my own unique agency if I'm not unique? Our universe appears to be made of the same few particles interacting with the same few forces everywhere. So if it is infinite, the mechanical motions of these particles are going to reproduce me making every possible choice available to me infinitely many times. It is going to happen. Even without invoking the Many Worlds Hypothesis that I don't really understand, I, or some being indistinguishable from me, am going to make every "choice" available to me. I don't see how that is really choosing--at least not in any sense that I'm willing to call free will. Maybe free will is just a (molecular and biological) computer program in my body taking in the various inputs and deciding what output is best for me as best it can. Maybe that is the only definition that makes sense. But maybe, if the universe is finite and I am unique, there is still hope for my soul.

. . . long enough for today. This looks like a multi part review, after all.