Saturday, 22 November 2008

Comment Commentary

My astrophysics expert Pause was good enough to school me last week on some of the finer points of what is known about the Big Bang, and upon being asked kindly placed his explanation in the comments section of the relevant post.

I asked him to do that, aside from the fact that smart people who know their stuff should always be listened to, so that I could ask a question that reading his thoughts inspired, which I don't think I've ever considered before. I hope Pause doesn't mind me hacking up his words (well worth reading in their entirety):

However, there is one deeper problem, and that's what created the manifold/brane/hypersurface/field that the universe itself was created from. You can already see the problem: it leads to the same infinite regression as 'who created the creator' (or even 'if this is a simulation, so are the people who made it').To the best of my knowledge (which is very limited at this level of quantum cosmology), no one's made a significant attempt to go back a step further than what created the universe (yet); we have enough trouble just supposing (read: inventing) various fields and branes in order to explain all we can see rather than worrying about why they were there already. (There are some people with loose suggestions - not least science fiction writers - but nothing you would ever want to call a theory.) The current theories are too incomplete to do more than worry about which one is right, never mind what's behind it. In essence, I guess we're still too busy trying to figure out what 'god' is before we get to what created it; religious/philosophical thinking has a few millenia head start on science.

There are two things to say here. The first one is that, whilst I agree with Pause that the infinite regression problem is common to the scientific and religious views of universe-creation, the latter has another problem associated with it, namely the explanation of the complex by reference to greater complexity. Whilst the idea of infinite universes stretching in both "directions" might be unconvincing absent further information, it does at least avoid the need to keep upping the stakes with each iteration.

I have a more fundamental point than that, though. Why is the idea of infinite universes problematic at all?

When I was a kid I had a friend whose father had a PhD in astrophysics. One day, whilst driving us to the cinema, he told me that there was a theory being batted around that the universe might be curved, so that if you set off in a shuttle craft and never changed direction, you would theoretically eventually return to the same point.

My puny ten year old brain refused to accept this. As far as I could see, if the universe was curved, we were inside a sphere, which meant there was something outside the sphere, which must also be the universe, since the universe was everything. My friend's father was kind enough not to completely disembowel me on the subject, simply saying "You're taking observations you've made in your life and applying them to situations you shouldn't possibly expect them to apply to".

I still don't get the whole curved universe idea (though I have progressed to not understanding the theory, rather than thinking it's obviously wrong), but that isn't the point. The point is, if we can accept that just because we see the world in three dimensions and Cartesian geometry (unlikely as we are to consider it in those terms) it doesn't mean they can be applied to the mind-shredding immensity of our universe, then what other preconceptions are we bringing to the table that are entirely reasonable from our perspective, but idiotic on the scale of the universe, or even multiple universes?

I would argue that one unnecessary restriction we might place upon our thinking in this regard is that chains always have a start. We're born to a mother who was born to a mother who was born to a mother, on and on and on. But everything we see in this world leads us to know that there had to be, in one sense or another, a "first mother", who was created in some other way. Whether God placed her on the Earth having grown her from a rib-bone, or sprung from the womb of the last of the creatures that could still be considered our antecedents rather than ourselves, there was a time before human women existed, and a point at which that situation changed.

It is tempting to think of the universe in the same terms. Sure, maybe our universe was created by the destruction of another universe. Or maybe not even its destruction, perhaps one universe gives rise to another in some way that lies beyond our understanding right now. The point is that the idea that this should lead to us to the conclusion that there must have been a time before the "first universe" is based entirely on our observation that a system of repeated processes must necessarily have a first step. Stuck atop our cosy little globe we have witnessed that cause follows effect, and that time flows in only one direction, and so we assume the same is true across the history of the universes. Even just using the word "history" betrays the difficulties inherent in considering what goes on on the inter-universal level.

It might be tempting to apply this same thinking to the existance of a God. If we break away from the assumption that the chain of universes has a beginning, why can't we get away with imagining God simply was always there?

The key difference in the two ideas is that we already know the universe exists. We continue to make progress towards working out what processes brought our reality into being. Once we get to that point, the question of "Where did the first universe come from?" is relevant only because we believe it is relevant. "It had to start somewhere." Why? God, on the other hand, has a host of other valid questions attached to him/her/them, the most pertinent one of "Why should a God exist at all?". That's not a question limited by our observations, that's just an application of logic, which is different.

At least, that's where my head was at on Thursday night. I'm sure bigger and better thinkers than I am have come up with this idea long ago, and may or may not have already shot it down in flames, but I thought it was something worth pondering. I mean, if you're reading my blog, it's not like you have anything more interesting to do.


Pause said...

It's perhaps worth noting that the thing that gave birth to the universe (whatever it is/was) doesn't necessarily have a property we call "time", or at least not linear time; hence the very question "what came before what came before" doesn't necessarily even make sense in ways I'm not going to pretend I understand.

(Not that a pre-state of 'timeless chaos' (in the classical sense of the latter word) is a thing you won't find in some very old textbooks on religious thinking - the arrow of time is a very old concept, after all - but science has at least put it on a firmer footing. If "firmer" means "this is crazy talk, you daft boffins", anyway.)

But then, thinking about why anything should exist at all makes my head hurt more than anything else except trying to understand women.

SpaceSquid said...

"It's perhaps worth noting that the thing that gave birth to the universe (whatever it is/was) doesn't necessarily have a property we call "time", or at least not linear time; hence the very question "what came before what came before" doesn't necessarily even make sense in ways I'm not going to pretend I understand"

Yeah, that was part of what I was trying to get across. You need to check this universe in at the door before you start poking around the whole chain, which is pretty hard. Even the word "chain" is just something I'm using for convenience, whilst fully aware of how little the term could correlate to what we're trying to discuss.

Pause said...

So you did, sorry. That's what comes of posting while not getting any sleep because you're frantically packing all your possessions into cardboard boxes before the removal van (replete with irritated parents) arrives.

SpaceSquid said...

Congratulations on your escape!