To BEgin or not to BEgin? A cosmology question. - by Nicker
zombe on 12/4/2013 at 00:28
Quote Posted by Nicker
What does the word "universe" mean? It seems easy enough, it is everything.
That bloody term is used whenever its meaning is convenient to describe something - nearly always leaving out what the "something" is. For example: "universe" for a astronomer actually means "observable universe". Mathematicians have their own universes (although they tend to explicitly name them) - can not positively remember any tho (Hilbert's universe?). A bit annoying indeed. Anyway...
I think you mean Universe without limitations - truly everything. Including what was "before" the big-bang. All the things we know and all the things we do not know. Everything imaginable and non-imaginable.
In short ... quite a lot.
Unfortunately, clearly some of it is beyond or current ability to know nor understand - which means that all the ideas we have touching that wall of ignorance are highly speculative and very weak in the "actually knowing" department. But we have bloody heaps of them to compensate (which is the source of confusion i think). So, expect there to be lots of ideas to fill various holes of "unknown" and also expect them to occasionally contradict each other or be just bonkers (either truly or perceptually) etc.
Bottom line - we (or more humbly I) do not know. Do not try to spill them into one mold and hope to get some sensible consensus out of it - there isn't any. Just have fun exploring various ideas ... quite liked the 1D one that popped up here (never heard of it before).
Quote Posted by Nicker
Does the universe get so weird that even mathematics becomes ambiguous?
Ambiguous? Did you mean "incapable of describing" or something like that?
IMHO, no. For me, mathematics is just a means to express and explore relationships and are completely separate of any imaginable and non imaginable universe. If there is a relationship then the fact of existence of the relation is enough to say one can describe it - coming up with one might be mindbogglingly difficult (or, in case of humans, even mentally impossible via strict physical limitations of our current makeup).
Could mathematics fail - no. The ones inventing/discovering/applying it - yes, absolutely.
Quote Posted by Nicker
If the math can shoot straight in any reality, can we determine whether the question of our ultimate origin is either answerable or unanswerable (or another option all together)?
By "our ultimate origin" i assume you mean the origin of our universe that made it possible for us to spawn? Interesting question. Have thought about that myself too.
That is not the field of math tho.
Can we find out everything there is to find out about the universe - i think most likely No. Information one most likely needs tends to get lost (for example: given enough time everything outside of our galaxy [or thereabout] will become unobservable because everything is moving away a lot faster than light due to expansion of space itself). Still, "Most likely No" does not mean it is impossible - it might be possible to infer the missing pieces, if any, from the local makeup of the universe.
Best we can hope for, i think, is to have a pretty good idea that we are almost certain about - but still lack any real proof of.
faetal on 12/4/2013 at 01:09
A lot of the origin of these questions comes from our brains inability to process the idea of a complete terminus. Why can't it be that the observable universe and everything in it came from a moment of infinite energy and density and has formed due to the expansion and cooling of this energy? Why does this then have to be inside something else or part of a bigger system? I think in light of the fact that there is little above very wildly hypothetical wonderings (brane theory etc..) and no real evidence of a "next tier up", it might be best to assume for the time that the observable universe is all there is. Without something solid which can be put to the test, it all starts to get a bit hand-wavy and in my experience, seems to be driven largely by people's inability to accept the notion of there being nothing at all outside of the observable universe.
It is pointless to be concerned with some kind of ultimate truth (just because we can't evidence it, doesn't mean it isn't there etc..) which is beyond our reach, because as long as it is beyond our reach, it may as well not exist, or at least the nature of its existence isn't going to be confirmed by speculation.
demagogue on 12/4/2013 at 01:18
Since the most distant parts of the universe from us are "moving away" from us faster than the speed of light (it's really not moving that fast, but space is expanding so it looks like it is), we already know that there is more matter and space than what can ever be possible to observe, and it's expanding over time. So we can't say "the universe is only the observable universe" for at least that much; we know there's more than we can observe & maybe even know a good deal about what that much is (or should be).
faetal on 12/4/2013 at 08:29
The expansion is not new matter is it?
I was under the impression that it is just further cooling and expansion of the same point of infinite heat and energy which the observable universe cooled from.
When rolling out pastry, the increasing surface area isn't "new" per se.
It could be that I misunderstand or have missed a recent finding though.
Edit: sorry I just re-read your post and realised what you meant. Sure there is more universe than we can observe, but we at least know that there is a good reason to think it exists. Speculation about it without a solid means to test is not going to provide much in the way of conclusion though. I'm comfortable with the idea that we just don't know and maybe never will.
demagogue on 12/4/2013 at 14:00
I should have made a more general point, and used another example, to get to what's curious about the limits of observation, which is the holographic principle. It has to do with the limits of all observation and the connection between that and "reality"... And one example is exactly the out-going stuff past the edges of the universe.
But there's another thing in the universe which we can also never observe, the inside of blackholes. But it turns out blackholes have an amazing property where all the 3D information inside is encoded on its surface in scrambled 2D, the event horizon. (The edge of the universe has the same property with out-going stuff too; but it's easier to talk about with a blackhole.)
And then there's another amazing possibility that blackholes (tiny ones) are practically everywhere... And (if I understood it right) almost every particle has its own event horizon, even normal ones (something to do with a thought experiment where you keep confining it smaller & smaller until it actually turns into a blackhole). That would mean actually the entire universe, everything around us, is not observable directly, but is (or can be computed as) a projection on a horizon surface, a 3D hologram on a 2D surface. That's the holographic principle. (I think.) It's pointing to reality being or at least working like pure information, where a 3D reality and a 2D scrambled projection are the same thing... all just pointing to some "actual reality" that's just pure information that can be encoded however you observe it.
In any event whatever it is, apparently even the experts don't fully understand it, it's supposed to be just as fundamental (and crazy) as the other weird principles we get in physics, relativity, quantum leaps, uncertainty... It just puts the whole connection between observation and reality on a different footing that's just weird but apparently true in some deep way.
Edit: Here's a cool book on it I recommend: (
http://www.amazon.com/Black-Hole-War-Stephen-Mechanics/dp/0316016411) The Black Hole War: My Battle with Stephen Hawking to Make the World Safe for Quantum Mechanics
Description:
Quote:
At the beginning of the 21st century, physics is being driven to very unfamiliar territory--the domain of the incredibly small and the incredibly heavy. The new world is a world in which both quantum mechanics and gravity are equally important. But mysteries remain. One of the biggest involved black holes. Famed physicist Stephen Hawking claimed that anything sucked in a black hole was lost forever. For three decades, Leonard Susskind and Hawking clashed over the answer to this problem. Finally, in 2004, Hawking conceded.
THE BLACK HOLE WAR will explain the mind-blowing science that finally won out, and the emergence of a new paradigm that argues the world--this catalog, your home, your breakfast, you--is actually a hologram projected from the edges of space.
faetal on 12/4/2013 at 14:26
Sounds worth a punt. I'll add to my wishlist.
What I was saying earlier about reality being essentially equivalent to pure information with dimensionality, including time, being a processing artifact of human consciousness ties into holo theory to a large degree. Humans / observers just being a piece of recursive reality. Have you ever read about Boltzmann brains? The idea that a higher grade of observer spontaneously arriving in the universe might invalidate our reality? It's another thought experiment, but also very interesting.
Another interesting possibility is the notion that in a sea of nearly infinite random information, not only will the eventual probability be that something like us will occur, due to near infinite chances, but perhaps the reality that we perceive is just ludicrously complex apophenia - that our observable reality is just a hyper-detailed "face on Mars". This is sort of a spin on anthropic principle.
