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Shape of the Universe Determined To Be Really, Really Flat
StartsWithABang writes: You might imagine all sorts of possibilities for how the Universe could have been shaped: positively curved like a higher-dimensional sphere, negatively curved like a higher-dimensional saddle, folded back on itself like a donut/torus, or spatially flat on the largest scales, like a giant Cartesian grid. Yet only one of these possibilities matches up with our observations, something we can probe simply by using our knowledge of how light travels in both flat and curved space, and measuring the CMB, the source of the most distant light in the Universe. The result? A Universe that's so incredibly flat, it's indistinguishable from perfection. Which means it's probably even flatter than Kansas.
Not sure what OP is on about.
http://michaelsmith.id.au
Let us build dykes in the void outside the universe, and polder in some more vacuum !
Religous speak to God. Insane are spoken to by God. When all shut up, one can finally hear Shostakovich in peace
If its surface is flat, what good a wormhole will do?
"A Universe that's so incredibly flat, it's indistinguishable from perfection."
Except, the article goes on to state that at larger much scale it may not be flat. So, to claim "perfection" is quite misleading.
Although there are locally flat shapes that are finite (eg torus or klein bottle), it seems likely that the universe is infinite. The observable universe is still finite though.
Don't waste your vote! Vote for whoever you want, unless you live in a swing state it won't matter anyways
The universe is a communion wafer.
No one will ever measure the universe to be perfectly flat, because that would require a perfect measurement with no margin for error, not even by the smallest number you can imagine. With either positive curvature or negative curvature, there would be margin for error but the only number neither positive nor negative is exactly zero.
Don't waste your vote! Vote for whoever you want, unless you live in a swing state it won't matter anyways
How can the universe be infinite? It's only as big as the farthest particle/wave from the point of origin of the Big Bang. Past that it's anyone's guess, except if you include Space. However as most cosmologists think, there is no difference between space and the universe because they think one generates the other. The OP/Ethan is confused about this making the arguments too simplistic for further discussion.
I don't mind reading blog posts on the medium, but this is really not news. You might as well have included this wikipedia article with the others you linked: http://en.wikipedia.org/wiki/S...
So, who are the lucky bastards who get the Dolly Parton universe?
Table-ized A.I.
The assumption of GR is that space/time can be described as a smooth manifold - a manifold being intuitively something like a beach ball, donut or similar. Smooth means that when you look at a piece of the manifold at a sufficiently small scale, it looks more and more flat; it really is that simple, what makes it hard is when you introduce the technical tools you need to make precise calculations. So, since we don't actually know the size of the universe, perhaps what we can measure is that we are looking at a much smaller scale than we imagined.
But, some will say, how about the speed of light? The age of the universe is known, so if it started out in the big bang as a single point, it can only be a limited number of lightyears across, right? There are several things to say, that might rock that particular boat a little. Firstly, we don't know that the universe was just a single point in size - in fact, the way QM is interpreted, it seems reasonable to think it wasn't. Secondly, if inflation happened, the universe went through a phase when it expanded a lot faster than the speed of light. And thirdly, of course, the speed of light is only known to be the limit within what we know as vacuum in the space-time we observe now, it only limits how much of the universe we can see now; we have every reason to assume that there is a lot more of it than that.
Almost as if we are living in a holographic universe that is nothing but a three dimensional waveform of a two dimensional object. Oh that's right, that's what we are doing.
If cosmic inflation is now a fact, then what was the big deal about this?
n/t
- In Soviet Korea, only old people loose all their bases to Natalie Portman's petrified hot grits overlords.
..the author meant
Flatter than Keira Knightley in a sports bra !
Through the law of large numbers the two options seemed to be perfectly flat or perfectly round. We should just simulate it in StarLogo and go with whatever the turtles tell us.
All the way down...
Nobodies Prefect
Tidbits for Techs Technology Blog
When you combine time cube theory with electric universe theory you get a cubic universe plus an electric clock. The cubic universe is flat (in the cosmological sense), so if the two underlying theories are correct then the universe diverges from flatness by the amount of one electric clock.
However, pedantically speaking, that's "plus one electric clock per universe". So in the case of a multiverse, the theorem only indicates the average. But with judicious application of the Central Limit Theorem, the Pauli Exclusion Principle, the Heisenberg Uncertainty Principle, and a line of reasoning left as an exercise for the reader, we can confidently conclude the universe is probably approximately flat, for definitions of "confidently", "conclude", "the universe", "is", "probably", "approximately", "flat", and "definitions" which remain to be derived from first principles.
Read more about it on my blog, Starts with a Bump on the Head, which, as you may have guessed from the title, is written in atrophic dactylic tetrameter, like all good cosmological monographs and comic books.
Sheesh, evil *and* a jerk. -- Jade
I like this idea. Three dimensions only. X and Y for area and T for time to stretch it out. Simple, no?
The most meaningful discussion this post generated was one regarding the flatness of the state of Kansas.
With all due respect to Ms Knightly, her lack of buxomness while exercising is about the least interesting thing to discuss at this point.
Someone flopped a steamer in the gene pool.
No, it isn't. I like flat- or small-chested women. The only US-American girlfriend I ever had, was as flat-chested as Kansas' plains, and she was smokin' hot. Morale of this tale: flat is beautiful; the universe being flat, it is beautiful.
Religous speak to God. Insane are spoken to by God. When all shut up, one can finally hear Shostakovich in peace
How is this fitting with Big Bang? Should not a round universe be shaped?
I don't about flat but I'm a small boob man. Most size b are too much for me and I hate the big fake boobs more than anything else. I can't understand the attraction of big boobs at all. They look gross and become knee shooters when a lady gets older. Give me a nice pair of small firm boobs anytime.
The universe is all of space and time. We have not observed/measured/etc. most of the universe yet to determine its shape. The parts of the universe we have observed are flat. Until we observe more of the universe, we will not know if the universe is flat or not.
Choosing the lesser of two evils is a choice for evil.
Here's an explanation: The universe is a hologram
> This glass of water does not contain any whales.
> I got it from the ocean, therefore the ocean does not contain any whales.
This is the logic you are trying to represent.
The problem is, that as far as can be determined, what we have observed, is all that mankind will ever reasonably be able to observe on this matter.
So unlike the glass of water above, its like observing 99% of the lake and finding no lochness monster, then concluding there is no lochness monster.
It's turtles all the way down!
Since we apparently have a seriously large system that is flat what are the forces that would cause a flat universe to perpetuate itself? Rotation might offer an explanation but there is also the notion that some force pressing from the top and another force pressing from below might cause a flat universe. Let the speculation begin! If the universe is like a flat sea can the universe cascade over the edge?
You'd think based on what we know about smaller scale explosions that the universe would be spherical, but even explosions in a vacuum aren't perfectly spherical. The shape of the shrapnel field and gasses depends on exactly how the explosion occurs. Until we know how dark matter and dark energy affect regular matter and energy with respect to accelerating it there's no obvious way to determine what the shape of the universe would be 13+ billion years after its creation. Subtle imperfections in the initial, generally spherical, shape of the universe might be amplified by their interaction with dark matter and energy, resulting in the initial sphere becoming highly irregular as it expands in size.
I think the question could be attacked from two sides. We can examine the current shape of the universe (shitty, because we can only see what is possibly just a small piece of it which may prove insufficient to extrapolate an accurate bigger picture) and ask, "If it looks like this now, what must it have looked like in the beginning," or we can attempt to understand through mathematics and theory what happened in the beginning and then extrapolate what it must look like now. Either way, I don't think we'll have a generally-agreed-upon answer anytime soon. Dark matter/energy is a giant hole in our understanding of how/why things move in the universe, so first thing first, figure that one out then worry about the size and shape of the universe.
Buy your next Linux PC at eightvirtues.com
The universe is all of space and time. We have not observed/measured/etc. most of the universe yet to determine its shape. The parts of the universe we have observed are flat. Until we observe more of the universe, we will not know if the universe is flat or not.
Unless they say otherwise, if you hear physicists talking about the "Universe" they're probably talking about the observable universe.
That article and many others missed the point. What they thought they'd seen was evidence for gravitational waves during inflation. There are lots of other reasons to believe inflation happened.
Naa. Great huge hooters. Go for the big blubber bags. (And leave those nice small firm boobs for me. - 'Scuze me, is it getting warm in here?)
Does that mean I cannot blame anymore the space curvature for me being overweight ?
Don't you know it is now both immoral and criminal to think beyond the next quarterly report?
>science.slashdot.com
The problem is, that as far as can be determined, what we have observed, is all that mankind will ever reasonably be able to observe on this matter. So unlike the glass of water above, its like observing 99% of the lake and finding no lochness monster, then concluding there is no lochness monster.
What we have observed is what we can observe, and it may be all that we can ever observe. It does not mean that there is nothing else that can affect us. A better example is of someone stuck in a little cove, observing the ocean from that viewpoint, hence seeing only a fraction of it. As far as that person is concerned there need be nothing else anywhere.
Hey, how do you like Gods handiwork?
http://i.imgur.com/1nSMqI4.png
Breasts are just enlarged sweat glands that exude a fatty sweat. Seriously, that's all they are. They can be nice or unpleasant or anywhere in between to look at, but what makes them special for us homo sapiens are the contexts within we are watching them. On a stripper, "Good fun". On a woman we fancy, "Woohoo!". On a woman who fancies us? THAT'S where they become beautiful.
But they're otherwise just sacks of fatty sweats under a gland. Just like kissing someone is sucking one end of a tube half full of shit.
When you think about it that way, you realise it isn't the mere object you're interested in, it's the social context of personal interaction and co-dependent involvement that makes you like boobies and kissing.
...that the flat universe is being supported by 4 elephants, and that these elephants in turn are standing on the back of a giant turtle, who is cruising the quantum realm between universes looking for quantum fish and insects to eat.
Nothing in that blog post was new. It presents no new observations. The universe was not recently discovered to be flatter than previously though.
"And that, My Liege, is how we know the universe to be banana shaped"
Which means it's probably even flatter than Kansas.
The band or the state?
It must have been something you assimilated. . . .
Native Kansan here. There are actually several states flatter including Florida, Texas, and North Dakota:
http://www.theatlantic.com/technology/archive/2014/03/science-several-us-states-led-by-florida-are-flatter-than-a-pancake/284348/
A mathematical note: Tori can be flat.
If the universe (and here we are talking about the large spacetime structure, not any of the weird tiny compactified extra string dimension stuff) is globally flat, it can still have the structure of a torus.
The torus when viewed as a 2 dimensional space in 3 dimensions, is not flat-- it has some positively curved parts (think the outer edge of the donut) and some negatively curved portions (think the saddle like regions on the inner ring of the torus.) However, the total curvature (when I sum up all contributing curvatures) on the torus is zero. This is related to a mathematical fact that the total curvature of any surface is given by a topological quantity called the genus. In simpler terms, no matter how I deform the torus, the sum of the curvature will be zero. This is very different from the sphere, whose total curvature is always 2\pi.
So, a flat universe would imply that we cannot live on a 4 sphere, because such objects must always have at least some positive curvature. However, there are examples of tori that have no curvature.
In the 2 dimensional case, it is best to see this from the ``Pac-Man'' perspective. The pacman game is played on a flat surface, and whenever you head off the top of the screen, you arrive at the bottom, and whenever you go off the left side of the screen you wind up on the right hand side. This describes a possible shape for the universe, and this shape is the torus! To see this, imagine that you took the playing field, and glue the top and bottom sides together. That would give you a cylinder. Taking the left and right sides and gluing them together would give you a torus. Now that we believe the pacman game is played on a torus, notice that the original interpretation was a flat surface. So , there is a flat representation of the torus.
To avoid some confusion and people trying to draw flat tori in 3 dimensional space, it can't be done. Every surface viewed in 3 dimensional space will necessarily have some positive curvature around its maximal value. Sorry folks!
In fact, of all the 2 dimensional (compact) surfaces, the only one that has a flat representation is the torus. So, if the universe is compact (and 2 dimensional, which seems unlikely,) there is hope for a Pacman world.
By "flat" they mean "spatially flat".
Scientists have also determined that the universe also is flatter than Paris, but not flatter than Paris Hilton.
Well, measuring CMB for the curvature of the Universe is a bit like trying to guess the shape of a really large body of water, while underwater, by measuring the vibrations caused by the fish swimming in that same water. Basically, not enough data to truly conclude. However, NASA to the rescue! We'll probably know for sure by 2034 ish http://en.wikipedia.org/wiki/L...
We can see almost all the observable universe, from now until just a few hundred million years after the big bang. In other words, we can see most of the universe that there will ever be to see.
It's called inductive reasoning. And it's the basis of all science.
Seriously I don't get it, are they saying there are more dimensions?
The article shows images of 2d things being wrapped around 3d things. So are they not saying by extension that our 3d universe is potentially wrapped in more dimensions, otherwise how could it be anything other than 3d.
And a 2d universe can't bend because it is a f**king 2d universe otherwise it wouldn't be a ruddy 2d universe it'd be a 3d universe.
This sh*t doesn't make any sense.
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"Infinite" in actualized physical terms is meaningless
Set theory is the basic logic maths is built on, it didn't change much for over 2000yrs. About a century ago people like Cantor, Godel, Russell, and many others started looking at set theory and infinities. The line of enquiry culminated with Godel's incompleteness theorem showing that any and every set of things is dependent on something else outside the set, add what is outside the set and you still have something else outside the new set. Godel's discovery that maths is "incomplete" (contains unprovable truths) destroyed what Russell and others had been trying to do with their Principia Mathematica- show that all mathematical truths can be mechanically derived from a set of fundamental axioms (Newton's "clockwork universe").
In other words Godel discovered that (maths says) the Universe (with a capital U) is "turtles all the way down" (and up).
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
No, it literally does mean that nothing else can affect us. If we are affected, we can observe these effects.
..Keira Knightley
If we are affected, we can observe these effects.
Agreed.
No, it literally does mean that nothing else can affect us.
Absolutely not. We know only what we have observed and deduced in the limited life of the human race. Other things that we have not observed or deduced yet will emerge. But until they do, we don't know that they are there.
well... if we think of the big bang as the explosion of a giant sun or star... containing all our matter in this universe....
then yes... the most matter was in the middle of this star exploding in all directions..... but as the most matter whas
on the middle plane,
and if it was a star exploding, the lighting in this universe was taken over by different suns, not the exploded blackhole that no longer sheds light.
greets Suprcow
After all, we know minecraft is smoother than a bowling ball at the scale of the earth. If you expand minecraft out to the scale of the universe, which is flatter?
Now I've heard it all. Precisely where does the third dimension .. er.. fit, then?
nothing is dimensionless, "its" dimensionless only until we are able to measure "it" in a fine enough resolution.
That in about 100 years Cosmologists will be laughing at the fact that we thought the universe was flat.