Outer Space Thread

[doe_boy]

[SHOW]

It's a diagram of the Saturn V using only the ten hundred words people use the most often.

[jim]

pretty good explanation for us n00bs

http://io9.com/the-new-big-bang-evidenc ... 1547240512

12 seconds in, she said something like "towerelllrr" and I said [expletive] this [expletive] and turned it off. Her accent makes me sad the big bang even happened.

[jim]

An informal poll - what is your "hunch" on multiverses? At first, I thought multiverses were more fantasy than anything, but I've actually come around to think they are the most logical explanation. I don't know why, but I have a hard time wrapping my head around a singularity popping into existence or the fact that there was something that started without the concept of before. That's the model of the one universe, from a singularity arose the universe. "Before" that? No such concept. I realize that's a limitation of the human brain, and I'm not saying I refuse to believe that can't be true, but it just doesn't sit well.

Now, take the string theory/multiverse idea. The strings have always been there, there is no need to even contemplate a "before" because time related to strings don't have a start. Strings (or branes) float around and collide and form a new universe. This just seems more logical to me, I know I can't argue it because there are many people much smarter than I that don't understand it well it enough to convince other people that are much smarter than I.

But it just seems like it should be so somehow in my mind.

[thrill]

To me it's all so incomprehensibly big that no matter what form space takes, there's always the unknowable beginning of how something came from nothing, so one universe and the multiverse seem equally implausible to me. Yet here we are.

[jim]

Not really, you need a beginning with the one universe/big bang, but you don't need a beginning with a multiverse theory. It's just always been, and universes pop up and die out all of the time.

[thrill]

Not really, you need a beginning with the one universe/big bang, but you don't need a beginning with a multiverse theory. It's just always been, and universes pop up and die out all of the time.

Right, but what causes that?

[go birds]

please say aliens please say aliens please say aliens

[AWvsCBsteeeerike3]

I have the same problem with either explanation. For a singular universe, the question becomes, well....when did it start and what is outside? For a multiverse, the question remains, well....when did it start and what is outside. I guess the multiverse explanation just says that it has always been and there was no beginning, it just always was, but that still leaves the question of what is outside the multiverse unless the answer is it is infinitely large with no beginning, ergo infinitely old, and has no boundaries....in which case, it blows my mind as to wtf we're even talking about.

[jim]

I have the same problem with either explanation. For a singular universe, the question becomes, well....when did it start and what is outside? For a multiverse, the question remains, well....when did it start and what is outside. I guess the multiverse explanation just says that it has always been and there was no beginning, it just always was, but that still leaves the question of what is outside the multiverse unless the answer is it is infinitely large with no beginning, ergo infinitely old, and has no boundaries....in which case, it blows my mind as to wtf we're even talking about.

This is less mind blowing to me for some reason than a one universe popping into existence through some quantum fluctuation. If the fabric has just always been here, then no beginning, no boundaries, etc... We have this concept in mathematics that comes up all of the time, and while our brain can't get around the infinite way we certainly understand the mechanics of it on an abstract level.

What I think you have to agree on is *something* has *always* been. Whether it's some potential universe coiled up into a single point, whether it's some fabric with strings and branes that create universes all of the time, whether it's a supreme being that decided to create it - whatever you come up it seems to me philosophically that you have to have had something where there was no start.

It's one of the most basic questions the human mind tries to answer - where did we come from? And it drives you mad, doesn't it?

[Arthur Dent]

If time is linked to space in our universe, what is this independent clock running that tracks the evolution of the multiverse "before" the big bang. Not that I understand it, but I think something is fundamentally missing with stories that refer to things "before" the creation of the universe that are not extremely careful about defining what exactly that means. By the same token, what exactly is the "space" in which this multiverse expands and produces universes as bubbles supposed to be?

As for multiverses, I'm fine with them, and it blows my mind that it may be possible to find observational evidence of them. I'm not exactly sure how multiverses described in cosmic inflation theory relate to other proposals for multiverses that are supposed to, in some sense, "overlap" with our own. String theory, on the other hand, has gone on and on for decades with essentially no contact with experiment or observational evidence. That sort of approach seems more consonant pre-scientific philosophical approaches to understanding the universe with a lot of math thrown in.