this post was submitted on 28 Feb 2025
382 points (92.6% liked)

Science Memes

14150 readers
1789 users here now

Welcome to c/science_memes @ Mander.xyz!

A place for majestic STEMLORD peacocking, as well as memes about the realities of working in a lab.



Rules

  1. Don't throw mud. Behave like an intellectual and remember the human.
  2. Keep it rooted (on topic).
  3. No spam.
  4. Infographics welcome, get schooled.

This is a science community. We use the Dawkins definition of meme.



Research Committee

Other Mander Communities

Science and Research

Biology and Life Sciences

Physical Sciences

Humanities and Social Sciences

Practical and Applied Sciences

Memes

Miscellaneous

founded 2 years ago
MODERATORS
 
you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 9 points 1 month ago (2 children)

Is the radial scale logarithmic? Or is it even more compressed than that?

[–] [email protected] 6 points 1 month ago* (last edited 1 month ago) (3 children)

First thing I will point out is there is no known shape of the universe.

[–] [email protected] 10 points 1 month ago (2 children)

If we assume the hubble constant is the same in all directions, the farthest we'd be able to see would be a sphere, dictated by the time light has had to travel to us.

[–] [email protected] 7 points 1 month ago (1 children)

That's what I'm assuming the original diagram is showing, the "Observable Universe" in some sort of radically increasing scale.

[–] [email protected] 3 points 1 month ago

It'd be interesting to see what a log scale would look like for this. I'll see if I can find one.

Here's one.

Log scale diagram of the observable universe https://pablocarlosbudassi.com/2021/02/atlas-of-universe-is-linear-version-of_15.html

Looks like the image at the top is a bit condensed comparatively.

[–] [email protected] 4 points 1 month ago* (last edited 1 month ago) (1 children)

I'll admit, I'm not deep in astronomy but thats inherently misguided. In a 3d space, observing from a fixed point, all areas that extend past how far we can observe would not be the shape of the universe but just our range of "vision."

[–] [email protected] 3 points 1 month ago (1 children)

Thus the term "observable universe". Everything beyond our observable universe is being expanded away from us at faster than the speed of light, so nothing outside will ever reach us. Causality is completely and irrevocably severed at those distances so, arguably, anything outside the observable universe is not part of "our" universe.

[–] [email protected] 1 points 1 month ago* (last edited 1 month ago) (1 children)

My point is, it doesn't reveal anything about the nature of the universe only about the limited view we can observe. As far as form goes the form of a sphere is meaningless because it is true of anything in a 3d space that is looking out from a fixed point.

[–] [email protected] 2 points 1 month ago* (last edited 1 month ago) (2 children)

As I just explained, it's not really about observation, it's about causation. If two objects can never possibly interact, then are they really in the same universe?

Looking out in space is also looking back in time. Anything (roughly) that is further than we can observe in the microwave background would be further back in time than the beginning of time, and therefore doesn't exist at all in our universe. It's a bit brain bending.

[–] [email protected] 0 points 1 month ago* (last edited 1 month ago) (1 children)

I would say yes they are part of the same universe because if you changed your position it would reveal things you didn't see before and mask thing you use to see. Not that that is possible yet, but there are no laws of physics preventing it, only our super short life spans.

[–] [email protected] 2 points 1 month ago (2 children)

That's just it. The laws of physics, at least as far as we understand them, absolutely preclude changing our position in any way that would reveal anything outside our observable universe. Lifespans don't come into it at all. If you lived forever traveling at the speed of light, you would never achieve that change of position.

The cosmic background is the leftover "noise" of the big bang, and we observe it roughly uniformly in every single direction. So where did the big bang occur? Everywhere. Everything that exists is precisely at the center of the universe, right where the big bang happened.

It's all about the concept of spacetime. Spacetime isn't space and time considered together, it's a singular thing that operates by rules that we are ill equiped to comprehend intuitively.

[–] [email protected] 1 points 1 month ago

flat earth on a flat universe, MUFA make-the-universe-flat-again

[–] [email protected] 0 points 1 month ago* (last edited 1 month ago) (1 children)

The laws of physics, at least as far as we understand them, absolutely preclude changing our position in any way that would reveal anything outside our observable universe

I do not agree. I don't believe the laws of physics are the limiting factor.

[–] [email protected] 3 points 1 month ago (1 children)

The edge of the observable universe is moving away from us faster than the speed of light from our perspective. (Due to space stretching) So we'd need to go faster than the speed of light to catch up.

[–] [email protected] 1 points 1 month ago (1 children)
[–] [email protected] 2 points 1 month ago* (last edited 1 month ago)

You could also use a wormhole to travel to different universes. It 'breaks' the speed of light, so all bets are off.

[–] [email protected] 4 points 1 month ago (1 children)

Is saddle still the best candidate? Like when you move a circle across a circle you get a torus, and when you move a parabola across parabola you get a "saddle"

[–] [email protected] 4 points 1 month ago

I want a toroidal universe. Just so it can be eaten by an extracosmic Homer Simpson.

[–] [email protected] 4 points 1 month ago

obviously the eye of our universe is flat

[–] [email protected] 1 points 1 month ago

It's not really to scale at all. Look at the distance between earth and the moon in relation to the other planets.