Is the Universe moving?

[Hashi Lebwohl]

Consider this thought experiment. You are in a room with no windows. This room is in outer space so there is no gravity and the room is moving at a constant velocity with no acceleration, again making certain there is no gravity. You have no way to view or detect anything outside the room.

From your position inside the room can you determine if the room is moving?

Clearly the answer is "no". Since there is no acceleration vector there won't be "gravity" so you can't test for falling objects and/or determine the direction of your movement. In fact, if you picked up a block, held it in front of you, then let go it would float in midair in front of you. If you threw the object it would travel in a straight line until it hit something. You cannot determine that the room is moving because you have no external frame of reference.

We may consider the observable universe as the closed room. We have no external frame of reference against which we may measure or detect anything outside our closed room therefore it is impossible to determine whether or not the universe is moving.

It seems likely that the universe is moving, but it may be moving in directions that are impossible for us to detect either because those dimensions are so small we cannot detect them or we are moving through things outside the observable universe.

Final answer: it doesn't matter if the universe is moving.

[wayfriend]

As you point out, you could tell if your room was accellerating. You could also tell if it was moving in a circlular orbit. Otherwise, the fact that a frame of reference with a constant velocity is indistinguishable from a frame of reference that is stationary is something Einstein pointed out -- it's all relative [to the frame of reference].

But for the universe to move, it needs to be in a different place later than it was before. Which presumes that the universe is in a place. Which presumes that there is something outside of the universe which contains the universe. Which is a contradiction.

Sorry, Cozarkian. Not sure that anyone means "cluster of galaxies" when they speak of the universe. I think they mean what came into existence with the Big B. Which would be the Big E: Everything.

[Vraith]

We may consider the observable universe as the closed room. We have no external frame of reference against which we may measure or detect anything outside our closed room therefore it is impossible to determine whether or not the universe is moving.

It seems likely that the universe is moving, but it may be moving in directions that are impossible for us to detect either because those dimensions are so small we cannot detect them or we are moving through things outside the observable universe.

Final answer: it doesn't matter if the universe is moving.

I agree that SEEMS to be the state of affairs. It is definitely the state now in our thoughts.
but I repeat, some smart folk are starting to think otherwise.
Nevertheless, if the "room" has "walls"...as we have expanding, apparently "material" space...at some point, you can start testing the "Walls" themselves, and finding the "frame."
In the end, it may NOT matter at all. There really may be "nothing."

But I am certain, justified only by the fact that "nothing" and "boring" "not mattering" have never, ever, not once, been the actual results of good science.
It was discovered centuries BC that the Earth orbits the Sun. The people who knew it said, basically, "it's true, but everything else is for priests and philosophers."
Well, they were wrong. It mattered. It mattered a lot...and every groundbreaking discovery since has been even MORE important.

A demonstrably moving universe literally changes everything for everyone.

[Avatar]

I saw you coming a mile away, that's why I said a fourth dimension of space.

Time is a dimension of space. Or vice versa. It's really just a direction. (Oh, there's a thread on M-Theory in here if you're interested.)

But I don't disagree with you...we could be moving in ways we can't ever detect. But like Hashi said, it's immaterial.

In fact, I direct all out attention to TOM's signature.

--A

[Hashi Lebwohl]

But for the universe to move, it needs to be in a different place later than it was before. Which presumes that the universe is in a place. Which presumes that there is something outside of the universe which contains the universe. Which is a contradiction.

That is why I use "observable universe". The actual universe includes things that are not observable.

Vraith, what I mean by "not mattering" is this: if you cannot prove x but you also cannot disprove x, then thinking about x will result only in frustration. The only way out of that is to somehow think about x differently based on information you learned elsewhere. In short, perhaps the question "is the universe moving?" is the wrong question to ask. Perhaps if we can come to a better understanding as to how space is stretching then we can ask a better question.

[Cozarkian]

Sorry, Cozarkian. Not sure that anyone means "cluster of galaxies" when they speak of the universe. I think they mean what came into existence with the Big B. Which would be the Big E: Everything.

Ever heard of the Marvel multiverse, as in multiple universes? While each universe might still contain more than just a "cluster of galaxies," I think there is a legion of comic book fans that would disagree the word universe is an all-encompassing term for all of existence (even if that is the proper scientific definition).

For that matter, Covenant's real world and the Land are separate universes.

[Ur Dead]

/walks in

Is the universe moving?

Sure..

Found a deal on a new condo down the block.


/walks out..

[Avatar]

For that matter, Covenant's real world and the Land are separate universes.

Are they?

Anyway, aren't we talking just about our own here?

--A

[peter]

Seems to me that if you can set of towards it, and reach it (no matter if the time it would take would be all but infinite) without having to 'jump dimensions' or any stuff like that, then it's in our Universe. It might not be in the observable universe, but it's in the Universe.