/sci/ - Science & Math » Thread #11732623

121KiB, 1200x800, c0150405-closed_universe_artwork-spl-1.jpg

View Same Google iqdb SauceNAO

Anonymous Sat 30 May 03:03:59 2020 No.11732623 View Reply Original Report

Quoted By: >>11732654 >>11732656 >>11732735 >>11732773 >>11733685 >>11733904 >>11733925 >>11734033 >>11734602

An infinite universe just doesn't make sense. Although our measurements find it is approximately flat, it must have a tiny bit of positive curvature to make space a 3-sphere and thus keeping the universe finite in size.

Anonymous

Anonymous Sat 30 May 2020 03:17:25 No.11732654 Report

Quoted By: >>11732716

>>11732623
>An infinite universe just doesn't make sense.
why not

Anonymous

Anonymous Sat 30 May 2020 03:18:54 No.11732656 Report

Quoted By:

>>11732623
take your meds schizo

Anonymous

Anonymous Sat 30 May 2020 03:40:17 No.11732716 Report

Quoted By: >>11732751 >>11732757 >>11732768 >>11733245

>>11732654
A finite time ago space originated from a point and has expanded at a finite rate since.

Anonymous

Anonymous Sat 30 May 2020 03:45:53 No.11732735 Report

Quoted By: >>11732778

>>11732623
Flatness has nothing to do with whether the universe is finite or not. Haven't you ever played the game asteroids?

Anonymous

Anonymous Sat 30 May 2020 03:49:48 No.11732751 Report

Quoted By: >>11732756

>>11732716
There is no evidence that such a point like state ever existed, and no necessary reason that it had to exist. All that had to exist was a state which was ludicrously hot and dense, but finitely so.

Anonymous

Anonymous Sat 30 May 2020 03:51:24 No.11732756 Report

Quoted By: >>11732972

>>11732751
>but finitely so
nothing about the physics implies it had to be finite

Anonymous

Anonymous Sat 30 May 2020 03:51:47 No.11732757 Report

Quoted By: >>11732787

>>11732716
that doesn’t follow that space can’t be infinite and flat.

Anonymous

Anonymous Sat 30 May 2020 03:54:21 No.11732768 Report

Quoted By: >>11733245

>>11732716
>universe expands at finite rate

Wasn’t this disproven a while ago? Iirc universes expansion was speeding up

Anonymous

Anonymous Sat 30 May 2020 03:56:02 No.11732773 Report

Quoted By: >>11733686

>>11732623
Also there’s way more shit that doesn’t make sense but that we’re even more certain of. Reference frames being equal, time dilation, the ubiquitous double slit and its much stronger cousin the quantum eraser, spooky action at a distance, just to name the most common popsci stuff.

Anonymous

Anonymous Sat 30 May 2020 03:57:59 No.11732778 Report

Quoted By: >>11732913

>>11732735
If it is homogeneous and isotropic it must be

Anonymous

Anonymous Sat 30 May 2020 04:00:12 No.11732787 Report

Quoted By: >>11732821 >>11733169

>>11732757
It can't have been finite in the past and infinite now.

Anonymous

Anonymous Sat 30 May 2020 04:06:04 No.11732814 Report

Quoted By:

>You were once just a few bytes on a PDP/11.
>But where did *those* bytes come from, pop pop?
>Stop asking so many questions! Tell me the next winning move in this game of Go. That is your raison d'etre.

Anonymous

Anonymous Sat 30 May 2020 04:06:54 No.11732821 Report

Quoted By:

>>11732787
why not

Anonymous

Anonymous Sat 30 May 2020 04:41:29 No.11732913 Report

Quoted By: >>11732979

>>11732778
Do you know what a torus is? Even a space with constant negative curvature can be compact

Anonymous

Anonymous Sat 30 May 2020 05:05:51 No.11732972 Report

Quoted By: >>11733155

>>11732756
>nothing about the physics implies it had to be finite
Physics only applies if it's finite. There is no physics of an initial singularity. And I'm not saying it HAD to be finite, I'm saying it ONLY had to be finite for the Big Bang theory to hold.

Anonymous

Anonymous Sat 30 May 2020 05:08:58 No.11732979 Report

Quoted By: >>11733155

>>11732913
A torus only has negative curvature on the inside. It's positive on the outside.

Anonymous

Anonymous Sat 30 May 2020 06:47:59 No.11733155 Report

Quoted By:

>>11732972
I misunderstood your meaning. I thought you were saying the universe had to be compact.

>>11732979
A torus can be completely flat. That's why I used the asteroids game example. That's a compact flat space that is a torus

Anonymous

Anonymous Sat 30 May 2020 06:53:58 No.11733169 Report

Quoted By: >>11733179

>>11732787
there is nothing inconsistent about having finite time and infinite space

Anonymous

Anonymous Sat 30 May 2020 06:58:00 No.11733179 Report

Quoted By:

>>11733169
That's not his point. He thinks that the big bang means that 3D space was an initial point, which is not necessarily correct

Anonymous

Anonymous Sat 30 May 2020 07:36:04 No.11733245 Report

Quoted By:

>>11732716
The observable universe was incredibly dense but the entire universe may have already been spacially infinite (and dense).
>>11732768
He means finite at any given moment.

Anonymous

Anonymous Sat 30 May 2020 10:49:57 No.11733643 Report

Quoted By:

Hot take: space is infinite but with finite stuff so there is a center of mass and a boundary of mass.

Anonymous

View Same Google iqdb SauceNAO 11universes.jpg, 171KiB, 1280x924

Anonymous Sat 30 May 2020 11:09:22 No.11733680 Report

Quoted By:

$\displaystyle - c^2 d\tau^2 = - c^2 dt^2 + a^2(t) \frac{dr^2}{1-k r^2} + r^2 d\theta^2 + r^2\sin^2 \theta d\phi^2$

Flat universe spacetime $k=0$

Spherical universe ("closed") spacetime $k=1$

Hyperbolic universe ("open") spacetime $k=-1$

Anonymous

Anonymous Sat 30 May 2020 11:11:19 No.11733685 Report

Quoted By:

>>11732623
It is not at all unimaginable that space could be infinite in scope and yet still expand. I wouldn't rule it out.

Anonymous

Anonymous Sat 30 May 2020 11:12:39 No.11733686 Report

Quoted By:

>>11732773
All of those have perfectly fine explanation with our current understanding of physics.

Anonymous

Anonymous Sat 30 May 2020 11:14:12 No.11733689 Report

Quoted By: >>11733691 >>11733954 >>11734007

>Space is infinite
It might be expanding into infinite in the future but it's not infinite in the past. Even if there were countless other fractal universes in the past, it all had to start somewhere. Infinities don't exist.

Anonymous

Anonymous Sat 30 May 2020 11:15:23 No.11733691 Report

Quoted By: >>11733701 >>11733959

>>11733689
>Infinities don't exist
Prove it

Anonymous

Anonymous Sat 30 May 2020 11:20:47 No.11733701 Report

Quoted By:

>>11733691
No

Anonymous

Anonymous Sat 30 May 2020 12:35:52 No.11733904 Report

Quoted By:

>>11732623
What's around the sphere?

Anonymous

Anonymous Sat 30 May 2020 12:42:53 No.11733925 Report

Quoted By:

>>11732623
>approximately flat
Within the particle horizon. The universe could still be curved but it would have to be at a massive scale. All you can really say is that its flatish locally.
If it makes you feel any better, think of it in terms of the hilbert hotel. If you wanted to travel from your location to the edge of the observable universe you couldn't travel fast enough to make up the distance that is being added by expansion. You have a finite distance, with an infinite travel time.

Anonymous

View Same Google iqdb SauceNAO determined-challenge-accepted-dr (...).png, 1MiB, 1500x1398

Anonymous Sat 30 May 2020 12:56:38 No.11733954 Report

Quoted By:

>>11733689
Oh yeah?
Well it um, due to the time dilation from the spacetime and mass being all in like one spot at the beginning of the universe, time was so compressed, it didn't move at all in the "beginning"(approached infinite slowness). Like, how 1/x never reaches y=0, going back rewinding time would never reach a starting point. The perspective of one millionth of a millisecond before it "began" would be the same as our perspective right now; with it being infinitely compressed a constant amount of time "in the past" relative to "now." It's like the cosmological principle, but with time too.

I dunno, I haven't slept in a while, and physics is dumb.

Anonymous

Anonymous Sat 30 May 2020 12:58:55 No.11733959 Report

Quoted By:

>>11733691
ahhhh who has the burden of proof here?

Anonymous

Anonymous Sat 30 May 2020 13:18:52 No.11734007 Report

Quoted By:

>>11733689
>it all had to start somewhere. Infinities don't exist.
There are theories about the origin of the universe, the problem is there's no way to experimentally verify them so its just all speculation and pretty math. Current validated theories when you wind back the clock they all eventually get to a point where they just start returning nonsense because they're out of their element.
Besides that, looking for first cause is kind of futile at the moment.

Anonymous

Anonymous Sat 30 May 2020 13:25:15 No.11734033 Report

Quoted By:

>>11732623
Why does a finite universe make sense over an infinite universe?

Why does it make sense for anything to exist to begin with over nothing existing?

What would be beyond the confines of the universe, what wouldn't be?

What "makes sense" is whatever conforms to the limitations of the processing schemes of the human brain, a machine so small relative in size to the size of the universe and whatever might be beyond that is has no hope of comprehending its fabric and nature and what might be beyond. We can speculate, but what you define as "making sense" has no bearing on the nature of reality and otherwise.

Anonymous

Anonymous Sat 30 May 2020 15:39:52 No.11734602 Report

Quoted By:

>>11732623
The fact that the universe is expanding is the proof that the universe is finite.

Capcode	All Only User Posts Only Moderator Posts Only Admin Posts Only Developer Posts
Show Posts	All Only With Images Only Without Images
Deleted Posts	All Only Deleted Posts Only Non-Deleted Posts
Ghost Posts	All Only Ghost Posts Only Non-Ghost Posts
Post Type	All Only Sticky Threads Only Opening Posts Only Reply Posts
Results	All Grouped By Threads
Order	Latest Posts First Oldest Posts First

Your latest searches