are there any boundaries to the universe?
400393
Hm - depends what you believe.\n\nI was taught (admittedly decades ago) that the Universe was infinite (in three dimensions) but bounded (in a fourth dimension).\n\nTo illustrate: the surface of an football is infinite (in two dimensions) but bounded (in a third dimension). A very flat insect (representing a two-dimensional life-form) can crawl in a straight line forever - therefore, from his perspective, it's infinite. It has no end.\nBut obviously we can see that the footbal is bounded in a dimension in which the insect cannot move.\n\nSo, the answer to your question would be:\n  yes, there are boundaries to the universe, but\n  no, we can't reach the "ends" because there are no ends in any sense we can understand them.
626622
The universe is an indefinite entity.It is bounded by 'nothing' even in the strict sense of modern physics.
33684
The Universe is boundless, yet finite.  So you could never exit the Universe.
90394
The current theories have predicted how large spacetime is, and many Astrophysicists are now working on finding who is beyond our universe. \n\nSo no, space is not infinite in the sense that most people think of. Outside of our universe is still a mystery, but keep in mind that there is not three demensional space outside of our universe, and no time, either.
3031
The universe is big enough to contain over 100 billion galaxies, of which the Milky Way is one. It is also expanding. Since it is growing larger, it can't be infinite, since infinitely-sized things can't become larger than infinity.
1159722
Well - the universe is infinite in so far as it can have an infinite distance.  However, if you take the classical approach, you can assume that the universe is at LEAST twice as wide as the distance light has travelled in the billions of years since the Big Bang, or moment of creation.  The reason is that the Universe contains all things, and it's width can be measured as the point between the two things at greatest distance from eachother.  The greatest distance between any two points is the distance between the first two photons that headed off in opposite directions at the time of the Big Bang.  Those photons still exist, and are still making their lonely trek through the unimaginable black nothingness at close to two hundred thousand miles per second.  So yes, I do believe the universe is that big.  At some point, you can view the positions of those photons more as a variable in some giant computer.  Their distance from everything else is actually pretty much irrelevant, since there is nothing out there for them to interact with.
312883
Yes.\n\nThere is so much of this universe that we do not know.
53803
According to modern physics, yes. Any infinite universe would actually contain an infinite amount of data, and thus would be aware of its own existence as well.If, however, you define universe as 'infinite' or 'everything' then no.
264754
Think of the universe as a giant bubble. Outside the bubble is nothing. nothing exists. no space. no time. Even though there is an edge to the universe, you cant reach it. If you started at the earth and went in a straight line. you would eventually come back to the earth. Also, we are not the only universe. there are other bubles. too. they are in the same nothing as ours. But you could not travel to other universes.
235823
I would say that there is no edge. The matter in our solar system is constantly being pulled and shifted by gravity fluxes, and if you were to drift further out you would run into another solar system similar in design to ours, just varying in scale. Because as humans we can only fully understand information that has a start and finish does not mean that there are borders to all things.
449942
As far as we know, the only "wall" is the event horizon of the observable universe, the events beyond it from our point of observation are too far away to have their light reach us given the age of the universe. This "wall" of observation is approximately spherical (mod the local curvature) and is continually expanding at the speed of light. Every observation point in the universe has its own event horizon/observable universe.\nOtherwise, there is no evidence to think that the universe is anything but infinite. Recent observations of the cosmic microwave background give us information that the cosmology of the universe is flat, ie. planar. This does not tell us whether the universe is compact or not. The only other types of cosmologies that agreed with Einstein's equations were spherical and hyperbolic.\nFor more information, see the source.
722611
the universe is constantly expanding although the rate is slowing and never reaches zero.\nexperts believe that the universe is finite yet has no edge, just like the surface area of a sphere. this could imply that if u reached one 'end' of the universe, u would end up on the opposite side or something like that
719656
the univesre is finite and unbounded.\nthat is at this particular moment matter and radiation exist till some position and not beyond that, that is there would be places where nothing has reached yet, this can be thought of as some kind of boundary. but this boundary keeps expanding with time.
1056226
The Universe cannot be infinite, because it is expanding, which points to its origin where everything began at the same point, namely the singularity of the Big Bang.  Therefore, if it is expanding, it is bounded.\n\nHowever, it is thought that it probably doesn't have an edge, much like the Earth doesn't have an edge.  If you started in a spaceship and went in a straight line, you would eventually end up where you started, much like if you started at the North Pole and went in a straight line, you would end up back the North Pole.\n\nThe reason: although you would be going in a straight line on the 2-D surface of the Earth, that line is curved in the 3rd dimension.  So, if spacetime is curved in the 4th dimension, you could be going in a straight line 3 dimensionally, but it would be curved 4th dimensionally.
747259
To find out whether there is an end or an edge to the universe we first need to know what is the shape of the universe.\n\nMost 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.\n\nThe 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.\n\nFinally, 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.\n\nWhat 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.
720625
the boundaries of the universe are a snow-globe. we exist in the snow globe of something much larger then ourselves. the stars are just the pieces of glitter that float when you shake it and then fall. the billions of years in our universe is just a few seconds in the life of someone who shook it up and now watches the snow fall.
1027618
It is quite possible for the universe to be both finite and without a boundary. No wall, but still it doesn't go on forever. Here's a way of visualizing it. Imagine that nomatter which direction you choose, you will eventually get back to your starting point if you go far enough in a 'straight' line. Impossible? Free your mind. It happens in two dimensions on the surface of a sphere. While it currently looks like the universe really is infinite, such three dimensional spheres were models used for finite universes until the data showed they are probably wrong.