It's Stephen Hawking's 70th birthday today. A lot of the coverage has been marveling at how he's overcome the odds by living this long with Lou Gehrig's disease. I imagine that when I'm that old or when I'm buffeted with such health challenges that's not what I'd like to be at the center of discussion.
I'm going to take a chance that that's Hawking's view too and instead commemorate his birthday with a question concerning Hawking's work that's been bugging me for a couple month's now (longer even than why we exchange gifts on Christmas and not Epiphany - which, in response to some questions, I really had scratched my head over since before Christmas).
Earlier generations perhaps knew Hawking for his black holes work, but by the time I got familiar with him he was well into obsessing over the grand unified theory issue. Even in Black Holes and Baby Universes and A Brief History of Time, Hawking talked a lot about this - but lately it seems like the only time he isn't talking about a grand unified theory is when he pauses to upset religious people by saying something controversial about God or to generate prime-time news fodder by saying something about aliens.
What's the big deal? Hawking has said that a theory of everything (as I understand it, GUT that incorporates the gravitational force too) would be the "ultimate triumph of science". Why?
I want to be clear about what I am and am not curious about here.
I am not asking why a brand new discovery would be cool. I know that. Obviously finding out something new about the universe is in and of itself important, particularly something this fundamental.
What I am asking is why a single theory for four things would be better than discovering that four things were actually explained by two theories. Or even that in reality we need six theories to best explain these four phenomena.
Is it simply the uniqueness of the number one that makes him so excited about a "theory of everything"? And if that's all it is, is that really a responsible way for a scientist to think about things?
That's really what I'm asking.
I'm also asking, of course, if there's a technical reason for why we should be excited about either a grand unified theory or a theory of everything - because there may be a technical reason I'm not aware of. Is it that we expect that there should be a theory of everything, but we just aren't able to nail it down yet? If that's what it is - if we know it should be there somehow, but haven't figured it out - that would make sense too.
But as it stands I'm not quite clear on why Hawking is so adamant about this. It seems to me we should want to understand the world effectively, regardless of how many distinct relations it takes. Right?