If nothing can go faster than light, shouldn't we be able

Yes.

>>7689988

You can't accelerate beyond the speed of light from any given reference. However the universe's expansion is different, it's expanding everywhere at once. Space itself is expanding, which is different from objects moving through space.

Pretty weird.

>>7689988
if at 1e-32s the observ.universe was grapefruit-size that is an expansion speed of 33000c

>>7689998
But expanding INTO what?

>>7690003
I've always also thought about this. Because if the universe is expanding, wouldnt that make the universe finite?

>>7690007
Well the universe is finite. However according to science there is no 'outside' the universe. If that doesn't make your brain run and hide I don't know what will.

>>7690007
I've heard an explanation that was basically "it's not expanding, it's stretching"

becoming less dense essentially. that way it could still be infinite(or not)

>>7690015
Science says no such thing. Stupid humans do.

Fuck them.

>>7690015
if you travel far enough to the universe, you'd end at where you began, like around-the-world trip?

>>7690015
Thats exactly whats making my brain run and hide! But doesn't you usually say that the universe is infinite? And also, if the universe is expanding, and expands faster the further out you look, wouldn't that mean there is a 'center of the universe'?

>>7690020
seems like not, all measurements indicate a flat spacetime

>>7690023
And? Who gives a fuck.

Why must spacetime meet itself? Simply being flat doesn't imply infinity.

>>7690022
not really. I mean I suppose but the 'center' would be changing all the time.

background radiation from the big bang does not support the classical big bang with a singularity. it instead supports a uneven distribution of energy to matter and even the possibility of heavy atoms being produced in the big bang not just hydrogen

light takes time to travel even with the classical version of the big bang the distance light needs to travel creates diffusion

the seemingly empty space sometimes has stuff in it like gas that can affect the visibility of light much like on earth with the atmosphere and particulate matter can further reduce visibility

your also only talking about 14 billion years for light to travel from one point and reach earth super diffused and not even be noticeable and/or not even make it here because of distance or line of sight not being achieved for the entirety of the trip light takes since objects are in motion

>>7690022
>time for some geometric nonsense

So the idea is basically take the cartesian space, all 3 dimensions. You are at (0,0,0), and given some scale factor (however you want to measure distance) there is a star at (1,1,1). The space itself is infinite in all directions.

Now, divide your scale factor by 10, the star is now at (10,10,10). The space is still infinite, and yet everything is further apart.

When cosmologists say that space seems flat, that is literally what they mean, it acts as the Cartesian Coordinate system. Infinite in all directions, but that does not mean it isn't able to expand. Now, imagine you live in a universe where the scale factor can change over time. Things either get closer together or further apart. This was the observation of Hubble, and we call the scale factor a(t), and Hubble's Law is a*/a = Velocity / Distance

https://en.wikipedia.org/wiki/Hubble%27s_law

So, no, the idea that space is infinite, and it can expand, are not incongruous, it's just weird when you first think about it. You have to realize when cosmologists say space, they mean both the physical place where everything is, and the abstract geometric notion of what a space can be.

>>7690036
Thanks for the explanation - though I still think that its quite hard to visualize

>>7690023
https://youtu.be/7ImvlS8PLIo?t=38m

>>7690081
I view the question of a deity as irrelevant, so I suppose functionally I'm an atheist, and even I find this guy's arguments to be wanting if not outright obnoxious.

Why do this? I get it, religious people and people of different beliefs contrast their fields and lives. I get it, these might start shit. But why focus on something so boring? This incessant and mindless fight against "religious" ideas. It makes myopic people. It gets in the way.

His quote of Einstein at the end, "God" suffixed with "[sic]". That's not what sic means. This is what Einstein said, it isn't up to you to decide what he "really" meant. Fuck off.

>>7690081
"We will be lonely and ignorant but dominant. But we in the united states are used to that."

Fuck you in the ear ass wipe. No seriously Couldn't stop slamming America every 10 mins throughout an entire video about science. It's possible to be too hip you shitheel.Hope he dies in poverty

>>7690148
>m-muh feeling bs
who cares. respond to the flatness

>>7690173
>m-muh feeling bs
who cares. respond to the flatness

>>7690196
Flat doesn't necessitate infinity.

>>7690007
>>7690015
>>7690017
>>7690022
>the universe is infinite
I think the confusion here is arising from this. The AGE of the universe is finite but the volume is infinite. Just saying the "universe" is infinite or finite is leaving out necessary information. Basically this >>7690036

>>7690224
>but the volume is infinite.
This is what I'm disagreeing with. It might be temporally infinite, but likely is not spatially infinite. I don't see why it would be.

>>7690226
How could it be temporally infinite? We are observing expansion, and we can track the expansion back to the CMB. We can extrapolate this and see that the universe started it's expansion no later than the big bang. Now, you're right that it isn't correct to assume spatial infinity, but unfortunately there's no way to test for spatial infinity/finiteness so it's up to interpretation. The age of the universe is however known to be finite because we can backtrack the expansion.

>>7690237
Some sort of looping, or mashing in on itself, or shared aspects that aren't strictly part of only what we consider our universe (best thought as linked, or spillover affects). Maybe this is what affords the appearance of probabilistic phenomena.

There are things we can't measure. We just can't. It was too long ago and the actual mechanics behind it could be obscured, no different than the way the big bang etc would be obscured if we lived much later. Expansion is irrelevant in this case, it'll just do whatever it does regardless of how long it's actually been at it. We'll look at it and impose our own illusions on it regardless, like we do with everything and anything else.

>Now, you're right that it isn't correct to assume spatial infinity
I'd like to at least know this before my death. If we can find a way to devise a means to test and verify if the universe actually has some sort of granularity. Base, fundamental, granularity. This implies something about the machinery of the universe itself. The universe as a platform that affords everything else the ability to be at all.

Kind of want to know if it's quantized. At that point, my intuition to say true circles cannot exist, would be correct.

>>7690003
Objects expand in space. Space is not an object, so the implicit logic that something must expand in a space doesn't apply.

>>7690007
No. If you split up space into an infinite amount of finite pieces and expand each piece (increasing the volume of each piece), the total volume is still the same (infinite). You can't always apply the logic of the finite to the infinite.

>>7689988
>If nothing can go faster than light
ambiguous and false assumption

>>7690226
>volume
> universe
choose 1

>>7689988

Laymen's logic but pretty much correct. The universe at times did expand at superluminal speeds. It's expanding superluminally now... at distances greater than about 14 billion lightyears. Do the math on the metric expansion of space.

Spacetime clearly isn't speed-limited in whatever 'space' it's embedded in.

>>7690003
I think this should help
https://www.youtube.com/watch?v=XBr4GkRnY04

I was thinking the other night that maybe the speed of light might be more important than people think
Like maybe it's connected to time itself and shit

I wonder what would happen if the speed of light was halved for three seconds.
Would anyone even notice anything?
Would the entire universe just combust instantly?

I really wanna know

>>7690003
That's not how higher dimensions work.
Your primate brain is deceiving you.

>>7690784
If c was cut in half for 3 seconds we would see the doppler shifts of galaxies become redder. Anything going faster than c/2 away from us would be invisible. It would appear as if things gained speed out of nowhere for 3 seconds, and this effect would seem to ripple out starting from us and ending at the edges of our observable universe. It would definitely be detectable.

>>7690800
How do they work? (genuine question)

>>7690018
Autism

>>7690003
Your mom's vagina.

>>7690845
I don't fucking know, I'm a biologist. Cosmology is just a hobby to me. I'm only at the point where I understand that much of this is above me.

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>>7690020
>if you travel far enough to the universe, you'd end at where you began

Exactly but not like you imagine traveling on a sphere.

One hypothesis is a Poincaré dodecahedral space.

" In 2003, lack of structure on the largest scales (above 60 degrees) in the cosmic microwave background as observed for one year by the WMAP spacecraft led to the suggestion, by Jean-Pierre Luminet of the Observatoire de Paris and colleagues, that the shape of the universe is a Poincaré sphere. In 2008, astronomers found the best orientation on the sky for the model and confirmed some of the predictions of the model, using three years of observations by the WMAP spacecraft. However, there is no strong support for the correctness of the model, as yet. "

https://en.wikipedia.org/wiki/Homology_sphere

http://physicsworld.com/cws/article/news/2003/oct/08/is-the-universe-a-dodecahedron

>>7690034
>it instead supports a uneven distribution of energy to matter and even the possibility of heavy atoms being produced in the big bang not just hydrogen
On what basis? The recombination spectrum hasn't been detected.

>the seemingly empty space sometimes has stuff in it like gas that can affect the visibility of light much like on earth with the atmosphere and particulate matter can further reduce visibility
The universe is optically thin at such long wavelengths. Yes there is scattering but it's completely insignificant. Saying there is diffusion so X will be supper scattered is bullshit, you need to know the diffusion coefficient to say that.
The fact that we see high redshift galaxies again supports the view that the universe is optically thin even at optical wavelengths.

>>7690237
>unfortunately there's no way to test for spatial infinity/finiteness

What is flatness?

>>7691222
The inverse of the Reiman curvature tensor

>>7690925
So how can you say that they don't work like that? (no, this ain't a genuine question.)

>>7690224
>but the volume is infinite
Citation needed.

2 options.
A) This is one universe among many 'bubbles in champagne analogy. Possible proof is hotspot area in cosmic microwave background (intersection of earlier universe).
B). The 'onion' universes analogy. Where 'ours' is in fact one of an ever expanding, ever creating, set of universes. The onion theory allows for the expansion, the lack of fragmentation of the fabric of space-time that should occur with accelerated expansion (and for me personally) fits with some postulates about the 2D nature of space-time thatcare incompatable with a 3D universe.

So if space is infinite, but objects within it are moving away from each other does this imply that there is some critical distance equal to the age of the universe times the speed of light, outside of which there exists absolute nothingness because nothing has had enough time to travel that far?

>>7689988
Light is considered the fastest thing within our universe, however, the speed it travels at is actually pretty slow when traveling through the whole universe. Those stars we see in the sky are actually reflections of light that existed thousands of years ago and are presently reaching us now. (But within speaking in the terms of physics, no matter how I move relative to something, the speed of light is always the same). So has the universe started expanding and the speed of light? Well I do believe that can potentually be possible, but you have to take into consideration as to the way space expands; it's moving in all directions all at once. Whether or not it's expanding faster than light is something we don't know and can't observe right now.

>>7692559
I guess a better way to phrase the question is to say are particles "stuck" in space with space expanding around them like raisins in a muffin as it bakes. In which case you would expect to find some distribution of particles no matter your position in space out to infinity, however this implies that either the big bang is wrong and all matter was not concentrated in a singularity at the origin of the universe, or. If it was then these particles must have moved faster than the speed of light to account for uniform distribution throughout a universe with infinite volume.

Or does space expand independent of particles, in which case we would expect the universe to be infinite space with a sphere of radius equal to the speed of light times the age of the universe which contains all matter and energy. Leaving the sphere would be impossible because you would have to travel faster than light to do so, however in the sense that space exists the region beyond it would also exist

>>7692559
I like to think of space, as a big black void that is infinite in... Space. Hehe. And the universe as this, massive sphere shape thing that is constantly growing and growing and growing in size. Until it can no longer keep growing. So I believe what happens is that after trillions of years is that it slowly starts to decrease in size, and compact quicker and quicker and quicker until all the quintillion of stars and black holes go into a super-close, super-deadly free for all battle with each other. The universe is naturally as hot as inside of a thousand of furnaces at this point, everything is close together. Until finally after millions of years the universe condenses into one super massive black hole. Now, the black hole is constantly trying to release energy but it's hard when space itself is PUSHING on it like when you but your hand over a hot tub tube and the water can't come out. Until the black hole finally collapses into a nova of pure condensed energy and gravity, then space eats that too and waits out until all of the known atoms and photons in the universe.. Evaporate. BUT! Eventually the remaining smallest parts of the universe EXPLODE into another Big Bang, and the story starts over again. It was... A really crazy dream I had.

>>7692599
That's just wrong. The expansion of the universe is not matter expanding into empty space, the space between galaxies is stretching.

>>7692574
The muffin analogy is good. It does not imply there was no singularity (which is no longer accepted anyway). Because it's an expansion of space not a motion in particles can move as quickly as they would like.

Galaxies aren't stuck however, they can have motions relative to their pocket of expanding universe.

>>7692559
Nope. There is the horizon beyond which we can have no knowledge of but in standard cosmology it would look much the same as our universe.

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>>7689988
>Is this right?
yes
+ onestone was a fool and a traitor

>>7690237
Right but a perfect sphere CAN exist in space. Pi wouldn't be relevant if spheres, couldn't exist. And yet we have so many determining values which utilize pi in their formulas.

>>7692866
If spheres or spherical natures were impossible*

>>7692574
Velocity can never exist as distance.