557
Scumbag Universe (i.imgur.com)
submitted 1 day ago by [email protected] to c/[email protected]
you are viewing a single comment's thread
view the rest of the comments
[-] [email protected] 19 points 1 day ago
[-] [email protected] 56 points 1 day ago* (last edited 1 day ago)

There is no outside, by definition.

We also don't know for sure wether it's infinite, since we can only see the "observable universe"

[-] [email protected] 18 points 1 day ago

If we are considering "the universe" to mean the spacetime that we exist in, there could be an "outside," but we just don't know, and there's no indication of such an outside, or anything about what it would be like.

By way of infinite spacetime, yes, there is only a part of spacetime that we can observe, because the farthest part is moving away from us faster than the speed of light. I seem to recall there having been some estimations of how large all of spacetime is, observable and unobservable, and that it has a finite size.

That said, there does not appear to be a limit to the size of spacetime. Based on what is currently known, spacetime is expanding, the expansion is accelerating, and there is no limit to the expansion.

[-] [email protected] 4 points 1 day ago

Honest question: if “nothing is faster than the speed of light,” then how could the universe be expanding faster than the fastest thing?

[-] [email protected] 15 points 1 day ago

So all space is expanding. Locally, that's "just a teeny tiny bit," and the force of gravity is plenty strong enough to keep things up to about the size of galaxies (maybe galaxy clusters) gravitationally bound. Andromeda, for example, is the only galaxy that is heading towards us.

But all of space is quite big. Over the vast distances of space, all of the "teeny tiny" local expansions add up. This means that the galaxies which are furthest away from us are also receding from us most quickly. This is not because those galaxies are moving through space; it's because of all the expanding space in between them and us.

The speed of light (in a vacuum) is the fastest anything can move through space.

[-] [email protected] 3 points 1 day ago

Would a fair, albeit crude, analogy be like when I fart and the gas forces my butt cheeks apart (the expansion between two objects)? (_|_)💨

[-] [email protected] 11 points 1 day ago

Crude, yes. Fair, no.

Consider a balloon. Uninflated, make a mark on opposite sides, and then make a third mark right next to one of those. When you inflate that balloon, the two points on opposite sides of it become farther apart because of the stretching of the whole balloon, but the two marks right next to each other don't become nearly as far apart, because they are only experiencing "local" expansion.

[-] [email protected] 7 points 1 day ago

I wanted to make a fart joke.

But I like your balloon explanation. That makes sense to me.

[-] [email protected] 5 points 1 day ago

We must sometimes succumb to our basest instincts.

[-] [email protected] 5 points 1 day ago

Don’t you mean our basic stinks?

Ok I’ll stop.

[-] [email protected] 2 points 3 hours ago

You ended on a high note.

[-] [email protected] 3 points 1 day ago

Fill the balloon with a fart

[-] [email protected] 2 points 1 day ago

Just fill the balloon with farts.

[-] [email protected] 5 points 1 day ago

It took my awhile to get it until somebody put it this way. The objects aren't exactly "moving" apart from each other, rather space in between them is expanding. So instead of thinking of it like a bunch of objects in a line being pulled away from each other, instead imagine it like a bunch of vector based objects random placed on an infinite canvas - now rather than moving the objects at all, try to imagine instead reducing the scale of all of the objects equally. Now of course this isn't perfect, as really what is happening is kind of the opposite, as the objects remain the same but the space between increases, but the relationship is the same here. So nothing is exactly "moving" in relative space, but everything is still expanding. Thus this expansion can happen infinitely without anything breaking the speed of light.

[-] [email protected] 7 points 1 day ago

Wait until you hear about relativity.

And also we don't know that C is the limit entirely, but it is so far. Also, we don't know if there are more dimensions in our reality or not because we cannot observe them. And no, I don't have much of a better answer.

Basically, we still know we don't know a lot, and we probably don't know a ton of what we don't know that we don't know. Also magic.

[-] [email protected] 4 points 1 day ago* (last edited 1 day ago)

ELI5: If I'm moving away from you at 50 KPH and you're moving away from me in the opposite direction at 50 KPH then after 1 hour we will be 100 kilometers away from each other even though the speed limit is 75 and neither of us broke it.

That's an extreme reduction but gets the general idea across.

[-] [email protected] 9 points 1 day ago

One day......we're going to observe the non-observable universe, and discover that it's exactly like this universe, except it"s last week. And then we'll do it again in a different direction, and it'll be next week. And we'll do it again, and again, and again, and again, and eventually figure out that everything we do, ever have done, or ever will do, only applies to THIS observable universe. And that we're one of an uncountable number of universes. Each a slightly different time than ours.

And no, it's not time travel. If you go to another universe, and kill Tom, then come back here, Tom is still alive. If you go back to that universe, Tom is still dead and you get arrested.

[-] [email protected] 4 points 1 day ago* (last edited 1 day ago)

The reason its called the observable universe is cause everything outside of it is moving fast enough away from us that it is physically impossible to ever get any light from outside of it. Everything that passes this point is gone from us forever. Relevant kurzgesagt about 4 minutes in

[-] [email protected] 3 points 1 day ago

Is that any different than the idea that every decision that could ever be made, is made, but has branched out into another universe?

[-] [email protected] 4 points 1 day ago

Yes, because those are not spatially connected.

[-] [email protected] 6 points 1 day ago* (last edited 1 day ago)

Itself. The distance between objects at inter-galactic scale is expending regardless of their relative movements.
P.S.: and the speed of expension is proportional to the distance between the objects.

[-] [email protected] 5 points 1 day ago* (last edited 1 day ago)

A great channel for topics like this.

This video goes into the expansion of spacetime as well as cover how internally those forces don’t affect local spacetime because of the mass/spacetime curvature.

Space DOES NOT Expand Everywhere

Although I have to agree with the top comment regarding this being my favorite channel I don’t understand. But the more I watch it the more I start to get a sense of a lot of it and I actually am understanding some of it

And yeah, we don’t know what, if there’s anything, it’s expanding into.

https://youtu.be/bUHZ2k9DYHY?t=537

[-] [email protected] 2 points 1 day ago

Nothing. It’s the same nothing that existed where we are right now, right at the moment the Big Bang occurred. It’s so nothing, that astrophysicists theorize that time doesn’t even exist there yet.

[-] [email protected] 2 points 1 day ago

Time is a property of spacetime, its own dimension. We have no reason to believe that time can exist without being part of spacetime.

[-] [email protected] 2 points 22 hours ago

Of course. I was simplifying and attempting to illustrate the difference between the vacuum of space and absolute nothingness.

this post was submitted on 25 Sep 2024
557 points (97.8% liked)

memes

9740 readers
1432 users here now

Community rules

1. Be civilNo trolling, bigotry or other insulting / annoying behaviour

2. No politicsThis is non-politics community. For political memes please go to [email protected]

3. No recent repostsCheck for reposts when posting a meme, you can only repost after 1 month

4. No botsNo bots without the express approval of the mods or the admins

5. No Spam/AdsNo advertisements or spam. This is an instance rule and the only way to live.

Sister communities

founded 1 year ago
MODERATORS