The Disappearing Universe 358
StartsWithABang writes: "If everything began with the Big Bang — from a hot, dense, expanding state — and things have been cooling, spreading out, but slowing down ever since, you might think that means that given enough time (and a powerful enough space ship), we'll eventually be able to reach any other galaxy. But thanks to dark energy, not only is that not the case at all, but most of the galaxies in our Universe are already completely unreachable by us, with more leaving our potential reach all the time. Fascinating, terrifying stuff."
speaks to our inner life (Score:4, Insightful)
the fact that seemingly inherent in our physical universe is a doctrine of the futility of outward movement (vis a vis reaching a sense of completion or boundary), to me, points to the individual quest for seeking oneself by focusing internally.
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one of the allures for me (and i think a lot of people intrigued with cosmology) is how we can interpret the findings as a macrocosm for our own personal microcosm of awareness and being.
the fact that seemingly inherent in our physical universe is a doctrine of the futility of outward movement (vis a vis reaching a sense of completion or boundary), to me, points to the individual quest for seeking oneself by focusing internally.
consider as well that as our galaxy redshifts from many possible planets of life we will never gain the knowledge of the inhabitants of those worlds, and by the same logic they could never invade ours.
terrifying? (Score:2, Insightful)
Really, folks, you need to stop being terrified by everything.
Re: terrifying? (Score:5, Funny)
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Seriously. Dark energy is hypothetical.
Heard it all before. Earth is flat, humans flying is impossible, break the sound barrier and you die, yadda, yadda...
Re:terrifying? (Score:5, Insightful)
Seriously. Dark energy is hypothetical.
Heard it all before. Earth is flat, humans flying is impossible, break the sound barrier and you die, yadda, yadda...
If you don't understand the difference between a line of uninformed idiots who kept saying "You can't have a rocket in space because there would be nothing to push against", displaying complete ignorance of Newton's laws, and the limits which are the consequence of well-reasoned scientific models such as C being an absolute limit of material acceleration, then you flat out don't understand the difference between a scientific approach and simply drawing limits out of your butt.
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Imagine how many quadrillions of intelligences exist in a galaxy the size of the milky way. Imagine how many of them will be destroyed by relativistic jets [nationalgeographic.com]
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If they are really intelligences, they would be gone before the jet starts spraying.
As for dark matter, that is probably just intelligences shielding off their stars with energy-collecting spheres.
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Suddenly, as a member of a Type 0 civilization, I feel rather stupid and insignificant.
Re:terrifying? (Score:4, Informative)
pardon me. I get my science from xkcd [xkcd.com], which recently stated:
Suppose there are 40 billion habitable planets in our galaxy, and every one of them hosts an Earth-sized population of 7 billion Ted Olsons.
There's your quadrillion. Are you a fan of hive minds?
Not so quick (Score:5, Insightful)
Physics graduate student here, and I'd just like to bring something into context before any ./ readers begin an existential crisis.
We don't *KNOW* anything about the dark matter/energy hypothesis yet. They are not well accepted theories like (classical) gravity or electromagnetism, but rather the best answer to questions we don't have any other way of approaching.
Warning: if you subscribe too heavily to these ideas now, you'll be way, way off base later when science starts finding better answers to the accelerating universe and other open questions. This stuff is great for discussion about philosophy and science fiction, but it is far from well accepted science.
Re:Not so quick (Score:4, Insightful)
From every description I've heard of "dark energy" it sounds like a kind of place-filler variable for something--as in, "This equation only works if we put in X, but we have no idea what X is."
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Maybe so, but that's almost exactly the same situation as when neutrinos were hypothesized to make the equations of some nuclear decays balance out.
Re:Not so quick (Score:5, Interesting)
From every description I've heard of "dark energy" it sounds like a kind of place-filler variable for something--as in, "This equation only works if we put in X, but we have no idea what X is."
Physicists brought us the dark energy hypothesis, not mathematicians. This is an important distinction: dark energy is not used to solve an equation, rather it is a phenomenon that we can indirectly observe.
Black holes, Dark energy, Zero point energy -- there are so many nascent concepts that hint at great disruption to our theories but that have not had the time to sort themselves out. Humanity rigorously worked on the concept of gravity for several hundred years before we had our Einstein.
Dark energy is... (Score:3)
Best description I have is that dark energy isn't the explanation, it's the description of the problem.
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We aren't even sure that they're unrelated. If gravity needs to be redone, the change might include both of them (or parts of both of them), e.g.
OTOH, coming up with something better than "We can't actually see anything causing these effects, but we see these effects..." is quite difficult.
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They are nearly 100% certain that there is galaxy amounts of invisible mass in these voids that cannot be seen. We can't detect dust of any kind, we can't detect black holes, yet we can detect huge amounts of mass. At this point, it is a fact that there is invisible mass.
Is it t
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I agree with you there, but any time I try to start the discussion with scientists at Fermilab, I've run into brick walls. They all have bought into dark energy as if it were as secure as our understanding of gravity.
Perhaps where you work it's not as well accepted, but in the little corner of the real science world I know, dark energy is some kind of science gospel.
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+1
You disappoint me , fellow physicist (Score:2)
Every damn hypothesis we have are only good as long as we do not find any better answer. Even the one you call better supported. Heck, 150 years ago you would probably have put newton in your list.
It is the basic reality in physic that we use what we have as hypothesis until a better theory or falsifying data com
Wormholes + a flat universe (Score:5, Interesting)
http://starchild.gsfc.nasa.gov/docs/StarChild/questions/question35.html
http://en.wikipedia.org/wiki/Shape_of_the_universe
But measurements are looking like the universe is flat.
You never know what scientific discoveries the distant future could hold, but at the moment it looks bleak for the concept of wormholes since the universe doesn't seem to be a hypersphere at all.
Re:Wormholes + a flat universe (Score:5, Interesting)
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I do not believe that what you wrote is correct.
Empty space is globally flat, but because gravity is a force with unlimited range no universe with any mass in it is globally flat.
At small enough scale every spacetime is locally flat, although that scale may be very small near a black hole. Only at the location of the singularity is it impossible to find a locally flat reference frame.
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The further you zoom out, the flatter everything appears in relation to everything else (globally flat). If you zoom way in, you can find numerous examples of arrangements across all three dimensions (locally non-flat).
Even if gravity is unlimited and radiates volumetricly, as you zoom out, there is no matter/energy for the gravity along the Z-axis to exert itself upon. And remember, you can still compare infinite sequences. One can state gravity is much stronger along the X-axis and Y-axis than the Z-axis,
Terrifying (Score:2, Insightful)
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Try Atkins.
All hope is lost (Score:5, Funny)
Now I'll never find the missing socks
...and this killed my interest in astronomy (Score:2)
At least in astronomy beyond naked-eye observation.
The universe is so vast that it boggles my mind. Just the distance between star systems in our galaxy is huge, then when you start thinking about the distance between galaxies, and then that there are clusters of galaxies... and the distance between clusters of galaxies. It's too much.
Not to mention that it pretty much puts the kibosh on things like intergalactic travel, probably even interstellar travel too.
Terrifying (Score:2)
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Re:Universe expanding faster than the speed of lig (Score:4, Informative)
How can that be? I thought nothing could go faster than the speed of light.
Or does the universe not have to obey it's own rule?
We're talking about expansion of space itself, not about a body traveling in that space.
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Likely the more correct statement is the maximum speed of light is the speed of gravity. So there are quite few particles that travel faster than the speed of light. Now when it comes to reaching other galaxies, seriously who really cares, there is just so much of this galaxy to explore, even living to really ripe old age of 10,000 earth orbits and travelling really fast from sun to sun, there are so many places, likely so many species and societies to explore, even allowing only 1 luna orbit at each locat
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Likely the more correct statement is the maximum speed of light is the speed of gravity. So there are quite few particles that travel faster than the speed of light.
I think you missed a few logical steps out there. Also, the names of these faster-than-light particles would be good to know.
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Also, the names of these faster-than-light particles would be good to know.
They are called "tachyons".
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They are called "tachyons".
And that almost certainly don't exist, which was my point.
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Space is nothing and nothing can go faster than the speed of light :-)
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This. They're already unreachable now. And until someone comes along and proves Einstein wrong, they're going to remain that way too.
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Re:Fascinating, terrifying stuff is news (Score:5, Insightful)
It's not really that fascinating or terrifying, though. "Based on our current understanding, we will never be able to reach certain galaxies." Ok, that's cool. We can't even reach another star system within our own galaxy at the moment, so traveling to other galaxies is a bit moot as is. We also know our understanding isn't complete, so it's entirely possible that something we don't know will allow us to travel to those galaxies.
Seriously, this doesn't feel like news. We've been working at the whole science and technology thing for what...ten thousand years or so? I say give it a million more and see where we are then, instead of cranking out sensationalist doom and gloom articles. Of course, all the doom and gloom articles tell you that we're not going to make it another decade, let alone a hundred thousand decades, so if you really feed into such things, then I'd say your outlook on the universe is far more terrifying than the article at hand.
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For Andromeda, just wait (very long term stasis recommended) it's comming at us, not sure it's a good thing.
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Re:Fascinating, terrifying stuff is news (Score:4, Informative)
That's not right; only from the light's perspective maybe.. it's still "only" traveling at 186kmph a second, it's not truly instantaneous. And I've never heard of the theory that suggests that if a person leaves earth and travels near light speed he'll be younger when he returns. He might not have aged, but not younger... unless he actually exceeds light speed.
Probably it was some type of a typo where he meant the returning brother is way younger than the brother that stayed (as opposed to just being "way younger" as stated in the OP's poorly worded response.)
Also, and playing Devil's Advocate a bit more, when the OP wrote this:
The time for light to travel from Earth to Andromeda is, essentially, zero (0) seconds
I'm reading it as the time that light (or anything travel AT the speed of light) "experiences" traveling from Andromeda to the Earth (or pretty much from any point A to any point B) is zero because of time dilation. True, it will take 2.5 million years (when measured from the POV of an observer not traveling at relativistic speeds), and travel is not instantaneous, but the traveler itself will experience time at a complete stoppage when travelling at the speed of light (or falling down a singularity) regardless of having traveled one inch or the entire width of the observable universe.
Re:Fascinating, terrifying stuff is news (Score:5, Informative)
Who could travel, faster than light.
She went out one day,
In a relative way,
And returned the previous night.
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As you approach the speed of light relativistic effects slow the passage of time.
At the speed of light, time cease to pass. Light in effect travels instantly from its perspective (in a vacuum, not sure what happens when its in a medium and slows down). We see the light move, but if you were a photon, your entire existence would be instantaneous from start to finish. Only an outside observer not moving at the speed of light would see light 'travel'.
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Not as far as the light is concerned. Photons do not experience time (due to time dilation). If you were able to travel at the speed of light (you can't), the entire future of the universe would pass by instantaneously (from your perspective).
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I've read that it's only 30 years, ship time, at one gee acceleration all the way, longer if you want to slow down and stop once there. Even the edge of the visible universe is achievable in a human lifetime (80 years IIRC) at one gee, of course by the time you get there the edge will be much further away.
Just need close to infinite free energy.
Re:Fascinating, terrifying stuff is news (Score:4, Informative)
No. That would be assuming you can go faster than the speed of light, without limits, which isn't the case.
Even if you were a massless particle, you would reach the speed of light in less than 1 year of accelerating at 1G, and then, you wouldn't be able to go faster.
Nope. GP was correct: note he said 30 years ship time You can accelerate at 1G indefinitely and you won't exceed the speed of light. You will asymptotically approach the speed of light, and time dilation will make the trip seem very short to the crew on board the ship.
Now calculate the reaction mass required.
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Yes, but this is a physics article and not a science fiction one so there is both a speed limit and no Wookies available.
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Say you wanted to go to Andromeda, not the closest galaxy but not exactly far on a galactic scale, At the speed of light that's still going to take 2.5 million years to get there, not really what most people would define as achievable, If we want to reach any other galaxy we're going to have to be going a hell of a lot faster than the speed of light.
Note that it is 2.5 million years from perspective of Earth. From perspective of the traveller, at speed of light the trip would be instantaneous.
I'll leave it as exercise for someone a bit more fresh with related math (or more motivation to Google) to calculate a more realistic figure: how much time it would be take to travel to Andromeda at constant 1G acceleration/deceleration, both Earth and ship time.
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Do you realize that the whole point of the GP's "exercise" was that you can't ignore relativity? It is due to relativity that the time observed by the traveller would be so little. If you are travelling at a velocity very close to the speed of light, in your own frame time is essentially standing still. You would get to your destination before you could blink your eye.
Now redo the calculations taking time dilation into account.
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At which point the rest of your post becomes pointless.
As you approach the speed of light, it takes more and more energy to go faster (actually this depends on the frame of reference). Regardless, you can continue to apply 1G of acceleration indefinitely, but not exceed the speed of light.
The 30 years or 80 years or whichever is ship time due to relativity, not observer time.
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Wrong on so many levels.
1) Yes, they are moving away from us at faster than the speed of light. This is well established [universetoday.com].
2) As long as the photons reach a region of space receding at less than the speed of light, we can see these galaxies. Good info here [stackexchange.com]
3) "And they fail to mention that they only way we're traveling through space is faster than light, some sort of weird quantum thing, by bending space, or via wormholes" None of which have been shown to exist. And there's some evidence that none of t
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Yup. At "worst" in an accelerating universe the galaxies would be receding from us at speeds that would tend asymptotically to 'c', but never at 'c' nor above.
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Nope. Distances between objects can increase faster than c because space is expanding.
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Although perhaps under such circumstances concepts like "receding" and "moving" become a bit more ambiguous than we're used to.
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Doesn't that require the appearance of an event horizon between these objects ?
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Yup. At "worst" in an accelerating universe the galaxies would be receding from us at speeds that would tend asymptotically to 'c', but never at 'c' nor above.
You haven't begun to imagine the worst. see my post above.
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The sky will slowly go black until it's as depicted in Greg Egan's "Quarantine" ? Well, except for our own galaxy being still visible and reachable... that's a consolation prize alright.
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Space itself is expanding and there is no limit to how fast that can happen. It can be at 1000 times the value of c if necessary.
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In this system nothing is moving faster than the speed of light but the effect is the same: a spacecraft trying to reach that galaxy would need to overcome all the expanding space between, and that would require a speed greater than
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Mind you, I'm an armchair cosmologist at best, so mine is more an interested layman's point of view; so I'm all ears (eyes) for an explanation. I'm not trying to refute the standard understanding here, or look smarter-than-thou, I just see what looks like a logical conundrum, what with my limited grasp of
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"But not if our Universe is accelerating. If something is receding from us right now at more than 299,792.458 km/s—faster than light speed—and it’s accelerating too, how could anything reach it?"
Isn't c the upper bound of speed in our universe?
is the upper bound of acceleration through space. Think of it this way. acceleration of a point through the 3d graph of space IS limited to C. But the lines of the graph itself that define the 3d location of things in space are accelerating from each other... the farther they are from each other the farther they recede. There is no limit to that recessional velocity. You will get to a point where acceleration being fixed simply can't keep up with the recession, so you'll never reach those parts.,
Re:Have some faith (Score:4, Insightful)
"I'm thinking wormholes, warp drives, hyper space."
All of which are are unproven theories. And could be proven to be impracticable (needing an energy the size of a star E stills equals MC^2) or impossible, or dangerous aka destroying the universe.
It may be the Speed of Light is the Speed limit that we cannot break.
In a world where Science Fiction is still fiction, and these wormholes, warp drives, and hyper space are meant as plot devices to move your characters into the story conflict of dealing with something alien. You find that these plot devices are made especially for weekly serial TV or movies with Sequels as you want to keep the same characters time and time again.
Now that said, it doesn't mean we should stop space exploration or trying to break the limits. Even if we could get a fraction of the speed of light say 1/10th the speed of light. We could travel our own solar system as well the sailors of old traveled the oceans. Generational ships can bring us to stars that are within 10 light years of year, and come back to earth without too much diversion of evolution.
Even without having to jump galaxies there is so much in our little neighborhod that we haven't explored.
As per Douglas Adams:
Space is big, I mean really big, you won't believe how mind boggling huge it is. You think it is a far way to the chemist? That is just peanuts to space, listen!
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Wormholes ok, they at least have a theoretical framework in modern science. Warp drives...well if you're talking about moving a space bubble relative to space itself. But since when did "hyperspace" become even a remotely scientific theory?
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I thought hyperspace was supposed to be a fictional alternate dimension ala Asimov. What has that got to do with the bending of spacetime by objects?
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Well I can accept FTL and wormhole travel so I can enjoy a good story. But just because I can imagine such things, it doesn't mean I think they exist. In fact the reason I can accept FTL travel in a science fiction story is that I'm not imagining it too hard. If I tried harder, I'd end up bringing in Special Relativity. Then I wouldn't be accepting FTL or wormholes (which have their own paradox-generating aspects) as plausible within the story.
I'd like to believe that I could be immortal. I want to be i
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Re:FTL or Wormhole Travel (Score:5, Interesting)
It's a bit more complicated than that. General relativity allows you to pick any reference frame, even one that is bent, stretched or distorted in some other way, and do your calculations in that reference frame.
You could pick a "normal" reference frame that obeys the special theory of relativity: speed of light constant everywhere, nothing can go faster, etcetera. Nothing wrong with that, but this turns out to be impractical: we have to pick some place to consider as the center of the universe (for example some place in our immediate neighborhood), and then find that the rest of the universe is moving away at very high speeds, approaching (but not exceeding) the speed of light. This means those galaxies are shrunk in the direction of their motion (Lorentz contraction) and time passes more slowly for them (time dilation). The further you "look" (the infinitely quick kind of looking which you can only do inside a theoretical model, not having to wait for light to get here so we can actually see stuff), the more things are shrunk and the slower time is ticking. At a distance of the speed of light ("c") times the age of the universe, things approach the speed of light and time is passing so slowly that the Big Bang is only just happening right now. In this way of describing the universe, with these coordinates the universe actually fits in a finite sphere around us.
That's a perfectly valid set of coordinates, but I think you'll agree it's not very practical. So physicists invented the cosmological model: imagine a bunch of clocks everywhere in the universe, flying at the same speed as the expansion of the universe (i.e. the same speed as average galaxies in that neighborhood) and ticking at whatever rate the local clocks are ticking at (not synchronized to ours). We define time at any place in the universe as being whatever is indicated by those clocks, not ours. So in effect we change the very definition of simultaneity, moving things from the future into today simply by changing the labeling. Also, imagine measuring sticks available everywhere in the universe, but just like the clocks flying at the same speed as the local expanding universe. To measure distances, we use those sticks instead of our own.
If we now measure everything using local (Lorentz-contracted) sticks and local (time-dilated) clocks, the universe looks completely different. It is truly infinite, the same age everywhere, and distant objects are no longer flat Lorentz-contracted pancakes but look the same as objects in our neighbourhood. Note that this is not a different universe, it's the same one but with different labels stuck onto objects.
Now, with this set of coordinates, it turns out that rays of light don't travel at a fixed speed "c" relative to us, but relative to the local clocks and sticks we used to define the coordinate system. It is still true that nothing can go faster than (local) light, i.e. you cannot overtake a ray of light, but a distant object certainly can move away from us faster than the speed of a ray of light in our neighbourhood. And if some alien over there were to try and shoot a laser beam our way, that light would never reach us because it is traveling towards us at the speed of light relative to the local "space" which is moving away from us faster, like a cosmic conveyor belt. Note that this conveyor belt is not real, it's just a product of our mathematical trickery refefining distances and times.
Of course you might wonder what happens to that alien laser beam in the first coordinate system, where rays of light all travel at the same speed relative to us. Well, in that system, the aliens don't exist yet because time in that part of space is moving very slowly (and has been moving slowly ever since the big bang). And since that part of space is still accelerating away from us ever faster and closer to the speed of light, local time comes to an asymptotic halt before the aliens ever get a chance to shoot that laser.
"Space itself" is just whatever we define it to be. By changing coordinates, we can move things from the past into the future or even into "never". It doesn't matter, it's just math(s), the end result is that we will never see that laser and we will never be able to reach that galaxy either.
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Mod parent up!
Most insightful thing I've read on Slashdot in quite some time.
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Magnificent post. I would mod you up, but SlashDot hasn't given me mod points in over a decade.
A dumb question for you, but one that I could not answer for myself by reading the article: How is it that the universe is accelerating away from center? Is there a huge amount of matter outside our universe that is pulling the outer bits away? Does the radiation from the inner parts create pressure on the outer parts? Or is there more relativity trickery at work here that I do no grasp?
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It doesn't matter, it's just math(s), the end result is that we will never see that laser and we will never be able to reach that galaxy either.
Infinity and void are incredibly powerful concepts, but I don't think "never" is particularly useful, especially when describing a universe for which our body of knowledge is so incredibly limited.
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M-M-M-MONSTER POST!!!!
Of enlightenment and knowledge peering past the veil of ignorance, cutting through the bullshit curtain of marketing, and bringing us along for the ride.
Thank you
I think I'm going to have to mull this one over (Score:2)
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This has no effect on gravitationally bound systems, which confuses me considering the whole universe, i would think, is a gravitationally bound system
Once an object reaches escape velocity, it is no longer gravitationally bound, no matter how close. You can think of the expansion of space time as a form of acceleration, and as long as two objects are gravitationally bounded, the gravity will over-whelm the expansion.
I wonder how that could affect the perceived orbits, if at all. I'm sure someone could contrive an extreme situation where one object is right at the break even point between gravity and space expansion, and instead of the two objects fall
Re:FTL or Wormhole Travel (Score:5, Informative)
The speed of light in a vacuum is always c. It doesn't matter if you're moving at 0.9c. If you shine a torch of light ahead of you, it will still move at speed "c".
What is meant here however is that there is no limit to how fast space itself can expand. So say we have two ends of a ruler 1 meter apart. After a while, space itself would expand meaning that the ruler will now be longer than what it was. There is no theoretical limit to how fast this can happen. It can be greater than c.
After a while, the space between the nucleus and electrons or within the nucleus itself will become too large, ultimately ripping apart for the fabric of reality itself.
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After a while, the space between the nucleus and electrons or within the nucleus itself will become too large
Won't the attraction between particles (or the quantum effects that keep electrons in their orbits) overcome this expansion? Or are you talking about a time when the accelerating expansion occurs so rapidly the even a "correctly spaced" atom gets ripped to pieces?
In that case it's not so much that too much expansion has occured (it's been occuring since the beginning of time, after all) but that it occurs too quickly.
Otherwise, the way you put it sounds like we're constantly being stretched and will eventua
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The attraction is a function of distance - the inverse square or whatever is the equivalent in the quantum world. The strong force in particular works only when the nucleus is tightly bound. Any relaxation in the distances should destabilize the whole thing. So yeah, we will eventually get ripped open. Even atom in our substance will disintegrate.
Re: expansion of space and dark energy (Score:2)
Hi bhagwad,
I think your post needs some clarification.
You wrote:
> After a while, space itself would expand meaning that the ruler will now be longer than what it was.
The expansion of space must be measured with respect to something. The usual idea is that space is expanding with respect to other properties of the physical world, e.g., the mean distance between electron and proton in a hydrogen atom. So, because your hypothetical ruler is made of atoms, the claim is that tomorrow it will take more of tho
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Perhaps he's a trifle more educated than you are?
Why, did he study custard and jelly with a minor in cream?
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I've met people who have been educated beyond the level of their intelligence. Are you one of them? Is the author of the post that triggered this discussion one of them? What proof can you offer for your opinion on these questions?
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The problems are a bit deeper than "we don't have the technology to do it". If we would be able to break these theoretical speed limits, this would automatically imply we would also be able to travel through time or at the very least send messages into the past. That would create a whole bunch of problems for concepts like causality, free will, grandfather paradox, etcetera. Not entirely impossible, I agree, but unlikely nonetheless.
Re:Maybe now, but (Score:5, Funny)
Unreachable with current technology perhaps, but who knows about the future?
The future, Conan?
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> Unreachable with current technology perhaps, but who knows about the future?
Unreachable with current physics known to man kind. Not just current technology.
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Or Beta.
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There are no limits to how fast you can travel. Physics allows you to go to the centre of the Milky Way and back in a day (well, as long as you avoid the black hole that is probably there). Of course the Earth will be somewhat older when you return, but for you only a day has passed.
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Math allows you to go to the centre of the Milky Way and back in a day....
Corrected that for you.
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Assume you could do 10*C it would still take 3000 years to the center of the galaxy
Nope. At 0.9999999c it will only take you 11.6 years to get to the center of the galaxy (plus, say, a year or two for acceleration).
Now, admittedly, this doesn't mean you'll be able to make it back in time to see how the world copes with the 2038 problem [wikipedia.org] - or even the events of Dune [wikipedia.org] - but travel time is not an issue.
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I am not saying we will find FTL travel method - but they are assuming we won't which is foolish.
There's a lot of evidence we won't. We would have found it by now if someone has discovered it in the future.
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but I think it's interesting how well it lines up with observation.
I think your example is tautological. It doesn't really imply anything about the shape of our universe. The only observation it lines up with is "space is expanding" which would be the same if the universe were on the surface of any other hyper-shape, wouldn't it?
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