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Can rotation solve the Hubble Puzzle?

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Re: Can rotation solve the Hubble Puzzle?

#11

Post by AnimalMuppet »

lumost wrote: post #8
hoseja wrote: post #2

Wait did nobody seriously consider rotation yet? Everything is rotating. Angular momentum is conserved.

Rotation implies a great many observables and properties of the universe. There would be a cosmic axis, which implies a cosmic center and a cosmic north. Both concepts that are problematic in an infinite universe. If the universe is in fact inside of a black hole of a different universe - some of these problems go away as the Hubble volume would be the finite boundary of the universe.

Are we in an infinite universe? I thought the current thinking was that it was finite but unbounded; that is, that it curved back on itself.

Re: Can rotation solve the Hubble Puzzle?

#12

Post by jl6 »

AnimalMuppet wrote: post #11
lumost wrote: post #8

Earlier quoted context omitted.

Rotation implies a great many observables and properties of the universe. There would be a cosmic axis, which implies a cosmic center and a cosmic north. Both concepts that are problematic in an infinite universe. If the universe is in fact inside of a black hole of a different universe - some of these problems go away as the Hubble volume would be the finite boundary of the universe.

Are we in an infinite universe? I thought the current thinking was that it was finite but unbounded; that is, that it curved back on itself.

That’s one speculative possibility, but we don’t know. It could be infinite, or finite with a boundary just out of sight (beyond the edge of the observable universe), or some other more exotic geometry. There’s no solid evidence either way.

My money’s on non-infinite, just because I’m not sure infinity is a well-defined concept outside of mathematics. We’ve certainly never observed any other infinite phenomena.

Re: Can rotation solve the Hubble Puzzle?

#13

Post by pfdietz »

AnimalMuppet wrote: post #11
lumost wrote: post #8

Earlier quoted context omitted.

Rotation implies a great many observables and properties of the universe. There would be a cosmic axis, which implies a cosmic center and a cosmic north. Both concepts that are problematic in an infinite universe. If the universe is in fact inside of a black hole of a different universe - some of these problems go away as the Hubble volume would be the finite boundary of the universe.

Are we in an infinite universe? I thought the current thinking was that it was finite but unbounded; that is, that it curved back on itself.

It's so close to flat that we can't tell.

Re: Can rotation solve the Hubble Puzzle?

#14

Post by XorNot »

jl6 wrote: post #12
AnimalMuppet wrote: post #11

Earlier quoted context omitted.

Are we in an infinite universe? I thought the current thinking was that it was finite but unbounded; that is, that it curved back on itself.

That’s one speculative possibility, but we don’t know. It could be infinite, or finite with a boundary just out of sight (beyond the edge of the observable universe), or some other more exotic geometry. There’s no solid evidence either way. My money’s on non-infinite, just because I’m not sure infinity is a well-defined concept outside of mathematics. We’ve certainly never observed any other infinite phenomena.

Except plenty exist - every electron is an infinite phenomena. They're point-like particles made up of no constituents. You can get infinitely close to an electron and still get closer to it.

Infinity extends both upwards and downwards in scale.

Re: Can rotation solve the Hubble Puzzle?

#15

Post by voidUpdate »

jl6 wrote: post #12
AnimalMuppet wrote: post #11

Earlier quoted context omitted.

Are we in an infinite universe? I thought the current thinking was that it was finite but unbounded; that is, that it curved back on itself.

That’s one speculative possibility, but we don’t know. It could be infinite, or finite with a boundary just out of sight (beyond the edge of the observable universe), or some other more exotic geometry. There’s no solid evidence either way. My money’s on non-infinite, just because I’m not sure infinity is a well-defined concept outside of mathematics. We’ve certainly never observed any other infinite phenomena.

It's only been a finite time since the universe was very small, so unless it's expanding infinitely fast, I don't see how it could be infinite

Re: Can rotation solve the Hubble Puzzle?

#16

Post by lambdaone »

XorNot wrote: post #14
jl6 wrote: post #12

Earlier quoted context omitted.

That’s one speculative possibility, but we don’t know. It could be infinite, or finite with a boundary just out of sight (beyond the edge of the observable universe), or some other more exotic geometry. There’s no solid evidence either way. My money’s on non-infinite, just because I’m not sure infinity is a well-defined concept outside of mathematics. We’ve certainly never observed any other infinite phenomena.

Except plenty exist - every electron is an infinite phenomena. They're point-like particles made up of no constituents. You can get infinitely close to an electron and still get closer to it. Infinity extends both upwards and downwards in scale.

Below the Planck distance, "closer" ceases to be a meaningful concept. Similarly, distances larger than the size of the observable universe may also be meaningless.

Re: Can rotation solve the Hubble Puzzle?

#17

Post by immibis »

voidUpdate wrote: post #15
jl6 wrote: post #12

Earlier quoted context omitted.

That’s one speculative possibility, but we don’t know. It could be infinite, or finite with a boundary just out of sight (beyond the edge of the observable universe), or some other more exotic geometry. There’s no solid evidence either way. My money’s on non-infinite, just because I’m not sure infinity is a well-defined concept outside of mathematics. We’ve certainly never observed any other infinite phenomena.

It's only been a finite time since the universe was very small, so unless it's expanding infinitely fast, I don't see how it could be infinite

Was the universe infinitely small or was it just extremely or infinitely dense?

Anyway, we don't actually know that, since we do not have a time machine. The theory that the universe used to be much smaller is something we infer based on the snapshot we see today, just like we infer rotation based on the snapshot we see today. Either one could yet be proven wrong.

Re: Can rotation solve the Hubble Puzzle?

#18

Post by dkural »

bostonwalker wrote: post #6

I seem to recall there was an article posted here recently which noted that galaxies have a preferred direction of rotation. Seems like the universe itself rotating could be a reason why?

That article is by a crank. People pointed out that he cherry-picked the galaxies, and no one else who looked at the data objectively saw any evidence of preference for a rotation direction.

Re: Can rotation solve the Hubble Puzzle?

#19

Post by [deleted] »

lambdaone wrote: post #16
XorNot wrote: post #14

Earlier quoted context omitted.

Except plenty exist - every electron is an infinite phenomena. They're point-like particles made up of no constituents. You can get infinitely close to an electron and still get closer to it. Infinity extends both upwards and downwards in scale.

Below the Planck distance, "closer" ceases to be a meaningful concept. Similarly, distances larger than the size of the observable universe may also be meaningless.

[deleted]

Re: Can rotation solve the Hubble Puzzle?

#20

Post by hnuser123456 »

lambdaone wrote: post #16
XorNot wrote: post #14

Earlier quoted context omitted.

Except plenty exist - every electron is an infinite phenomena. They're point-like particles made up of no constituents. You can get infinitely close to an electron and still get closer to it. Infinity extends both upwards and downwards in scale.

Below the Planck distance, "closer" ceases to be a meaningful concept. Similarly, distances larger than the size of the observable universe may also be meaningless.

The co-moving radius of the universe is about 3x larger than the observable universe, but I don't think there's any practical measurements larger than that. We don't know how much is beyond that because potentially a large chunk of the universe is already forever outside our past and future light cone.
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