What is the Universe expanding into..

[M Gregg]

Just for interest,

What is the Universe Expanding Into?

And

http://preposterousuniverse.com/writings/cosmologyprimer/dark.html

A poll has been set and it is multiple choice the poll is on going...please read the thread before voting..

Regards
M. Gregg

 

[Bonsai]

Should be one for the physicists amongst us to get their teeth into.

 

[SY]

We get into that around our sophomore year.

The real takeaway for the lay-folk is that there are questions which can be expressed in grammatically correct English which make no physical sense. We see that a lot here where people want to talk about specific electrons.

 

[Bonsai]

So, what is it?

Does space-time beyond the known universe compute to zero since time does not exist (if nothing's happening . . . does time exist?). What are the implications for mass-energy equivalence in the absence of time? I would assume beyond the known universe if would be nice and quiet - no thermal noise out there.

I expect SE to drop in any minute with an explanation

 

[SY]

I was referring to the first link, not the second. The whole dark matter question is really complex (translation: requires more general relativity and high energy background than I have ).

 

[Bonsai]

Well, you're ahead of me on the theory bit!

My simplistic understanding: unless time and energy are present, there is no universe as we know it. So, I have no doubt that the edge of the universe as we know it is where time and energy encroach.

 

[SY]

The whole point is that there is no such thing as "the edge of the universe." Grammatically fine, syntax fine, physically meaningless.

 

[SNR]

Throughout history very few have had the epiphany required to grasp, let alone or observe space time relationships.

The universe is not expanding, only our view of the universe is expanding. Einstein inadvertently makes this clear in his observations, which interestingly enough have no references.

I'm sorry but Hubble's conclusions are misinterpreted.
His experiments used locally earth based "2D" observations fail to utilize or understand Einstein's work.

You cannot measure the Earth's "speed" using Hubble's technique while sitting on it.

It's narcissistic behavior of some humans who subconsciously want to be the center of the universe.

Hubble's experiment performed on any planet will have the same observations.

The big bang theory let sciences progress while letting certain factions of society save-face. It's the Darwin or the egg theory.

 

[SY]

The universe is not expanding, only our view of the universe is expanding.

The data indicate otherwise.

You cannot measure the Earth's "speed" using Hubble's technique while sitting on it.

Grammatically correct, physically meaningless.

 

[Philosophil]

SY,

Wouldn't it be more correct to say "physically meaningless on the current model or theory"? After all, the notion of individual electrons might actually be meaningful on the older, planetary or billiard ball model, but not on the current model. Similarly, the notion of an edge to the universe might actually have a meaning in an Aristotelian or Ptolemaic model of the universe, but again not in the current one. Of course to the best of our knowledge we should take the current model as truthful to some extent, but that doesn't mean it must serve as the basis for the meaning of all terms or sentences, including a physicalist sense. Doesn't it make better sense to think of meaning as being context dependent and what might be meaningless in one context could be meaningful in another?

Phil

 

[JoeDJ]

There is nothing outside the the universe as "space" its self does not exist it is empty............ "space"

Only various form of energy and matter exist in non existing space
So, how can something that does not exist possibly have a boundary or a beginning or end?

Look at it this way... would a doughnut hole exist without a doughnut?

 

[Bonsai]

The whole point is that there is no such thing as "the edge of the universe." Grammatically fine, syntax fine, physically meaningless.

The 'edge of the universe' I think is simply a boundary within which time, space and energy are as we know it. Beyond that . . . who knows?

And yes, it is meaningless because our current paradigm cannot explain what may lie in a realm where some if the fundamentals as we understand it do not exist.

(And, no, I don't believe in ET visitations)

 

[SY]

Wouldn't it be more correct to say "physically meaningless on the current model or theory"?

Physically meaningless on the basis of experimental data. New models will undoubtedly take hold, but correspondence will hold.

 

[5th element]

Maybe it bears mentioning that there is a specific edge to the observable universe though. From what I recall there is more stuff beyond this point it's just that we cannot measure it in any way.

The whole 'what is space expanding into' thing is rather difficult to get ones head around. Because it just is rather than is a part of something else. So this absolute thing is just getting bigger into itself and it's increasing the rate at which it is doing it too. I can't quite get my head around it because it's a concept that we just have nothing to compare it to so it makes no real sense. But it is what it is.

Most things in physics can be made to make some kind of rational sense, but the universe expanding isn't really one of them. I mean at the point of the big bang it's possible that the entire universe was infinitely small and then to be what it is now. But then again if it was the only thing around at the time of when it was infinitely small then surely to it, it was infinitely large too

 

[sofaspud]

I guess you could say, in astrophysics even nothing is something.

 

[DUG]

"What is the Universe expanding into.."

Sound like a modern day version of an older question:

Where does the ocean water go when it flows over the edge of the world?

(IMHO)

 

[MisterTwister]

It's expanding into exponential horn. Once form is created, special announcement will be made through that horn.

 

[Absconditus]

According to Einstein, the rate of expansion depends on the average energy density of the universe.

From the second URL, my question is "from what and into what" does this expansion occur? if there was a singularity, wouldn't the big Bang have thrown out in all directions and with roughly the same force? If so, isn't our "universe" the outer edge of a very thick-walled expanding sphere?

As for the word "universe", maybe this is just reflective of human hubris? Just because we can't see it, and maybe never will, it doesn't mean that there aren't many more (possibly an infinite number) "universes" out in the infinity of space.


Abs

 

[SY]

If so, isn't our "universe" the outer edge of a very thick-walled expanding sphere?

Nope. That's the fun part.

 

[ArtG]

If you want a reasonable idea of what the universe “looks like”, ponder the comment once stated by an astrophysicist: Take a mobius strip, and conceptualize it in four dimensions.

Have fun!