Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Can rotation solve the Hubble Puzzle?

academic.oup.com

Post reply on HN
Print view View original

21–30 of 120 posts

Re: Can rotation solve the Hubble Puzzle?

#21

Post by ziddoap »

dkural wrote: post #18
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.

I looked around (Smithsonian, space.com, astronomy.com, etc.), but nowhere has any mention of people disputing the findings, do you have a link? Who is "people" in this case?

(I was/am skeptical just because it's a single-author study with pretty spectacular results, and have been keeping an eye out for any followups, but must have missed them)

Re: Can rotation solve the Hubble Puzzle?

#22

Post by iainmerrick »

ziddoap wrote: post #21
dkural wrote: post #18

Earlier quoted context omitted.

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.

I looked around (Smithsonian, space.com, astronomy.com, etc.), but nowhere has any mention of people disputing the findings, do you have a link? Who is "people" in this case? (I was/am skeptical just because it's a single-author study with pretty spectacular results, and have been keeping an eye out for any followups, but must have missed them)

This comment has a good summary of the debunking: https://news.ycombinator.com/item?id=43540635

It's unfortunately rare for this kind of straightforward falsification to make it into publications aimed at the general reader. "A lie is halfway round the world before the truth has got its boots on," as they say.

Re: Can rotation solve the Hubble Puzzle?

#23

Post by [deleted] »

dkural wrote: post #18
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.

[deleted]

Re: Can rotation solve the Hubble Puzzle?

#24

Post by AnimalMuppet »

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.

That's only if you view the electron classically, which is an inadequate picture.

Re: Can rotation solve the Hubble Puzzle?

#26

Post by atkailash »

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

[dead]

Re: Can rotation solve the Hubble Puzzle?

#27

Post by kstrauser »

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.

Why is that? I've heard this before but don't understand what it actually implies. Like, why can't 2 things meaningfully be half a Planck distance apart?

Re: Can rotation solve the Hubble Puzzle?

#28

Post by Galatians4_16 »

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.

>If the universe is in fact inside of a black hole of a different universe

The observation could also be due to an area of relatively high density inside an area of relatively no density.

Re: Can rotation solve the Hubble Puzzle?

#29

Post by ziddoap »

iainmerrick wrote: post #22
ziddoap wrote: post #21

Earlier quoted context omitted.

I looked around (Smithsonian, space.com, astronomy.com, etc.), but nowhere has any mention of people disputing the findings, do you have a link? Who is "people" in this case? (I was/am skeptical just because it's a single-author study with pretty spectacular results, and have been keeping an eye out for any followups, but must have missed them)

This comment has a good summary of the debunking: https://news.ycombinator.com/item?id=43540635 It's unfortunately rare for this kind of straightforward falsification to make it into publications aimed at the general reader. "A lie is halfway round the world before the truth has got its boots on," as they say.

Thanks.

I was hoping for something a bit more authoritative than a reddit comment being copy/pasted to HN (e.g. an actual retraction, or a paper directly disputing the findings), but I'm guessing most of the community just ignored the paper due to the history of the author.

Re: Can rotation solve the Hubble Puzzle?

#30

Post by Nevermark »

kstrauser wrote: post #27
lambdaone wrote: post #16

Earlier quoted context omitted.

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.

Why is that? I've heard this before but don't understand what it actually implies. Like, why can't 2 things meaningfully be half a Planck distance apart?

Imagine that at some small distance, space itself is quantum, so quantized. I.e. at the bottom, space is a discrete graph with incredibly small edges. Possibly very tangled and not even layed out in obvious dimensions over short distances.

We don’t know if that is the case. That is only one possibility.

But it seems very clear that whatever happens at the Planck distance or lower isn’t simple smooth space as we model it for larger scales.

Post reply on HN