Is universe a sphere?

Answer 1

It's not a sphere in 3 demensions.

Think in one less dimension. Say there are some 2 dimensional creatures. They can look left-right, front-back. They can't look up-down, have no concept of what that means.

They live on the surface of what we see as a 3 dimensional sphere. If they walk far enough in one direction, they return to their starting point. If that sphere is an expanding balloon, their 2 dimensional universe is expanding. Points marked on the surface are steadily moving away from each other.

As their 2 dimensional universe is the surface of a 3 dimensional sphere, our universe is like the surface of 4 dimensional sphere.

Answer 2

Most astronomers would like to know the shape of the universe too! There are three general possibilities. First, like your balloon, the universe might have what we call positive curvature, like a sphere. In this case, which we call a "closed" universe, the universe would be finite in size but without a boundary, just like the balloon. In a closed universe, you could, in principle, fly a spaceship far enough in one direction and get back to where you started from. Closed universes are also closed in time: they eventually stop expanding, then contract in a "Big Crunch." All the geometry that is true on a sphere is also true in a closed unvierse: parallel lines eventually converge (e.g. longitude lines are parallel at the equator, but converge at the poles), large triangles have more than 180 degrees, etc.

The second possibility is that the universe is flat. This kind of universe you can imagine by cutting out a piece of your baloon material and stretching it with your hands. The surface of the material is flat, not curved, but you can expand and contract it by tugging on either end. Flat universes are infinite in spatial extent, and have no boundaries. Parallel lines are always parallel and triangles always have 180 degrees. Flat universes expand forever, but the expansion rate approaches zero.

Finally, the universe might be "open," or have negative curvature. Such universes are sort of saddle-shaped. They are also infinite and unbounded. Parellel lines eventually diverge, and triangles have less than 180 degrees. Open universes expand forever, with the expansion rate never approaching zero.

What determines the shape of the universe is its density (and the Cosmological Constant, a sort of anti-gravity force allowed by General Relativity). It is difficult to figure out what the density of the universe actually is, but it seems that the universe is probably flat.

Answer 3

If I didn't read this question at 3:40 am, I'd go through my books and find the stuff I read, but off the top of my head:

There are theories that it could be all sorts of shapes.

Big Bang theory leads us to think it's a sphere, but it's not the best supported theory. String Theory... um... look it up and see what it says.

Observations of stars is interesting, because we are trying to measure based on the concept that there's a straight line between us and the things we're measuring. However, astronomers are considering the possibilites that some of the things we're seeing is REFLECTIONS of stars, which could be created by a Universe that is wavy or shaped like a donut.

It's a really good question, though, and I'm going to watch this question to see if anyone posts some links on recent research on the subject.

Answer 4

No. The universe is not shaped like a sphere, nor a cube, nor a toroid, nor no anything, IT CANNOT HAVE A SHAPE. Bcoz if something has a shape then, by implication, we are saying that it ends somewhere. but if it ends at some point, then the questioin : "In what is this universe contained?" cannot be answered. This paradox clearly arises because of the incorrect framing of the original question.
in other words, asking "what is the shape of the universe?" is fallacious.
The universe is like a misha doll : u open up the biggest one and there is asmaller [similar -- remember fractal nature of things? - God is the greatest Fractal Artist !] one inside. you open-up this 2nd doll and there is one yet smaller and so on. in the end, you open the smallest one and LO & BEHOLD !! THE FIRST [the biggest one ! ] DOLL IS INSIDE IT !!!
In other words, the microcosm is contained within the macrocosmos while THE MACRO IS WITHIN THE MICRO !!

THERE IS NO OTHER POSSIBLE SOLN. TO THIS PARADOX THAN WHAT I'VE GIVEN ABOVE.
[ATTN. : if anyone has got a better idea or wanna chat with me on this then email me at [e-mail]

Answer 5

The Universe is endless.
Our tiny minds cannot get a handle on its size,
so we try to give it shapes and boundaries, all of which is folly.
====================
NO. IT IS CALLED 'MAYA' - an illusion.
======================
Big Bang theory leads us to think it's a sphere,
but it's not the best supported theory.
===========================
Einstein said,
"remember gentlemen, we have not proven that the Aether does not exist,
we have merely proven that we do not need it (for computations)"!
====================
The “Big Bang” is abstract hypothesis.
Once upon a time, 20 billions of years ago, all matter
(all elementary particles and all quarks and
their girlfriends- antiparticles and antiquarks,
all kinds of waves: electromagnetic, gravitational,
muons… gluons field ….. etc.) – was assembled in a “single point”.
It is interesting to think about what had surrounded the “single point”.
The answer is :
EMPTINESS- NOTHING….!!!
Ok!
But why does everyone speak about EMPTINESS- NOTHING in
common phrases rather than in specific, concrete terms?
I wonder why nobody has written down this EMPTINESS- NOTHING in
the form of a physical formula ? You see, every schoolboy knows that
is possible to express the EMPTINESS- NOTHING condition
by the formula T=0K.
* * *
Once there was a “Big Bang”.
But in what space had the Big Bang taken place
and in what space was the matter of the Big Bang distributed?
Not in T=0K?
It is clear, that there is only EMPTINESS, NOTHING, in T=0K.
Now consider that the Universe, as an absolute frame of reference is
in a condition of T = 2,7K (rests relic radiation of the Big Bang ).
But, the relic radiation is extended and in the future will change and decrease.
What temperature can this radiation reach?
Not T=0K?
Hence, if we go into the past or into the present or into the future,
we can not escape from EMPTINESS- NOTHING T=0K.
Therefore it is necessary to begin to think from T=0K.
===================
Just accept that it is endless T=0K and try to understand...IT.
=========
http://www.socratus.com

Answer 6

Well universe cannot be described in just 3 dimensions! Universe is actually a space-time curve. But According to Einsteins Theory of General Relativity and The Uncertainty principle of Quantum Mechanics, the universe can be thought of like something without an end or beginning like the earth. But u cant call it a sphere.
Read Stephen Hawking's Book-Brief History Of time.

Answer 7

The Universe is beyond shape and size
It has neither chape nor size. Therefore the Universe is not a sphere. It extends beyond the limits of the sphere

Answer 8

No. The universe is endless. Only the planets are sphere.

Answer 9

It is endless,stll we can say it is a sphere with radius Infinity.Because for anything in this universe(which includes the universe too) spherical shape is the state of equilibrium.

Answer 10

NO. IT IS CALLED 'MAYA' - an illusion. The Universe is an illusion as illused as your mind. Try to reach beyond it, then you will see it. Your mind is a close up of the Universe. Try to travel, you can fly or swim. The moon around the earth, earth around the Sun and the Sun a/w solar system revolves another which your 'Science' could not name it. (you can name like milky way or else). The center on which Sun revolves taken another bigger circle and it goes on to the end of your mind's horizon.
Why do we bother for it?. You are born on earth, eat, drink and make merry, if you like, else if you want to know more, pray God. He would, of-course, direct you to know and create another Universe like this.(Yes, not joking).