Title: Re: Scale of the universe
Post by: wilykat on August 02, 2012, 02:26:43 PM
Begs one question: what is the size of the actual universe? The visible universe is 14 billion LY from Earth but is the true size actually infinite? Or would we run into something like a barrier (like a fish bowl iniverse)? Or would we loop from one side to other side?
We may never know it unless we get something that can do thousand light year per second or something insanely fast. (wormhole, warp, etc)
Title: Re: Scale of the universe
Post by: Jugbug on August 02, 2012, 04:46:23 PM
Interesting link, although I was kind of expecting it to show a white PCE at the very right.
I thought Asteroids answered that for us decades ago.
Title: Re: Scale of the universe
Post by: soop on August 02, 2012, 10:51:30 PM
Interesting question Wily. Firstly, your assumption about the "visible universe" is partly correct, and as nothing can travel faster than light (except perhaps tachyons), the physical universe should indeed be the age of the universe in lightyears x2 across (29.2 bn lightyears). However, remember, spacetime isn't flat so there the answer gets more complicated. That is to say that the distance required to get from one side of the physical universe to the other should be 29.2bn ly, but to an observer outside the universe, it would appear to be smaller. Think about space being lumpy custard, where the lumps are curves or kinks in spacetime. To the outside observer, it looks like the distance from one side of the custard to the other is uniform. But if you're in the custard, it will take you longer to move through the lumps, increasing the distance.
As to what's outside the physical universe, and whether that counts as "the universe" (and from my rusty latin, it seems it should), that's impossible to tell right now. I would posit that since space itself is infinite, that just as we went from planet to solar system to galaxy to universe, I suspect that one day (though I don't know how) we'll find that our "universe" is just one of many. (and that doesn't even count parallel universes)/
And as far as how big the universe is, I have no idea.
Title: Re: Scale of the universe
Post by: Tatsujin on August 03, 2012, 01:10:19 AM
great stuff..lol
we're so big and yet so small :D
Title: Re: Scale of the universe
Post by: Tatsujin on August 03, 2012, 01:29:19 AM
btw. reminds me of this very old animation from the border of the universe right into the humans smallest parts.
this was once broadcasted in the TiVi when I was about 8 or so. was very very impressive stuff for back then :)
Title: Re: Scale of the universe
Post by: soop on August 03, 2012, 01:36:51 AM
But you shouldn't be able to get to the other universes if they were physically located adjacent to ours, because even if the laws of physics were the same in each universe, the space in between would not have the same laws, so you couldn't cross it without:
1. Suddenly having no mass, meaning that every particle in your body would accellerate to the speed of light, after: 2. The strong and weak nuclear forces break down, allowing atoms to fuse, or more likely tear apart, unleashing the energy of trillions upon trillions of atomic bombs (specifically, around 45,166,059,675,000,000,000,000,000,000 of them) which: 3: wouldn't matter because energy would not have the same properties as it usually does.
Title: Re: Scale of the universe
Post by: SuperDeadite on August 03, 2012, 01:39:50 AM
Isn't there some new theory that our entire universe is actually inside a black hole? And the universe expands as more stuff is sucked into it? Meaning there basically is no end.
Title: Re: Scale of the universe
Post by: SamIAm on August 03, 2012, 02:01:42 AM
Carl Sagan breaks down dimensions and the size of the universe in a way everyone can understand:
Title: Re: Scale of the universe
Post by: Nando on August 03, 2012, 02:38:14 AM