Is it possible to define a boundry around the universe? If so, what lies outside the boundry?
132208
The boundry of the universe lies at the outer limit of expansion of the space-time continuum.  It's a popular misconception that the universe is expanding into space.  The truth is that space-time itself is expanding, carrying all the matter and energy in our universe along with it. I should also mention that the 4th dimension, mentioned in other answers is, in fact, time. It is already included in the whole time-space continuum. As for what lies "outside" the universe, the question is in one respect meaningless.  Since it is space and time that is expanding, there is no "outside" in any meaningful sense of the word.  All the space that exists does so within the bounds of our universe.  I know what you are trying to say is"What is our universe expanding into?" but again, that question cannot be answered meaningfully.  We can't even set up mathematical models that are more than speculation because the laws of physics as we understand them are applicable only within the framework of the T.S.Continuum they exist in. Some have speculated that there may be other universes that lie "outside" our own, and there is a body of mathematical models to support this idea, but the plain truth is, no one knows for sure. If such universes exist, they will probably function under differing "laws" than our own, and will be difficult, if not impossible to comprehend. As for what lies "between" universes-as it is "something"(for lack of a better term) that falls completely outside of any human experience or frame of reference, there are no words to describe "it."  You may as well call it the Tao- that's about as close to describing it as we will ever likely get.
173712
There is no answer to this question within the context of which it is asked.  The theory that the universe is finite but boundaryless is groundless at best having been built from many accepted, yet untried, pre-existing theories of the universe.  \n\nThis theory should be more approprately viewed as the culmination of everything we do not know about the universe, and is tied entirely to a singular perspective. Yet it is accepted as fact by many within the scientific community and elsewhere.\n\nBased on our current technological capabilities and observations of the universe we have no business asking science this type of question.  In turn it is irresponsible of science to supply any type of response with conviction and confidence.  \n\nTheories such as this one are no different than the assertions of any religion;  they require an enormous amount of faith to be accepted.\n\nBottom line:  your guess is just as good as anyone's.
134083
Size & volume of the current universe have little bearing on how "big" or "small" the singularity was at the moment this universe came into being, since the structures of the various sub-atomic particles that make up atoms and unltimately the "stuff" you have difficulty in "compacting" were not yet defined sufficiently for your question to have meaning.  Not that it's a bad question.  It's just in the same family as "well i know the Universe is infinite, but what's outside it?"\n\nStephen W.Hawking might be a good place to start.
131776
It could be possible but there is something called the cosmological principle that are a set of assumptions about the universe that prevents us from determining that.  Basically we need to assume, among other things, that the laws of physics, as they apply here, work the same in other parts of the universe.  Without this assumption we couldn't make any statements about the universe since it would be pure speculation.
208221
Outer space must go out forever, else there would be an end to it.  If there were an end to it, what would be on the other side of the end?\n\nI can live forever, and I'm not interested in the "outer limits."  Plenty of interesting things all around.
255034
In spite of what some yo-yo answered, the universe IS expanding, but whether or not it's expanding inside something else is absolutely and totally unknown. In the far distant future our science might have progressed to a point where we'll have the means to answer that question. Instead of driving yourself goofy over wondering what our universe is inside of, best to just try and imagine an absolute and infinite void totally without space, time, energy, mass, or anything else.
321917
Quite an interesting question.  Well, it's true that the Universe is expanding, has been expanding since the Big Bang, and always will expand.  Plus, it's been doing so at the speed of light, so unless there's some way for us to travel faster than that, we're already too late to actually go (or send something) and find out what it's expanding into.  Point B can never reach the end.  Having said that, we're fairly sure that 'nothing' is beyond space.  Space is expanding into nothingness.  Of course, this is a hard concept since most of space has nothing in it anyway.  Yet even  when space is empty, it's still considered 'something.'  This empty 'something' expands into the nothingness.  Confusing, I know, but I can't think of a better way to explain.  Anyway, I don't believe there's a container that would stop the Universe from expanding.  I suppose it could be theoretically possible, but I'm not sure how.  I believe it will keep on expanding forever.
495537
There is nothing called the end of the Universe. There are three possibilities of the shape of the Universe.\n\nFirst, the Universe might have what we call positive curvature like a sphere. In this case, the Universe is called "closed" and it has a finite size but without a boundary, just like a baloon. In a closed Universe, you could, in principle, fly a spaceship far enough in one direction and get back to where you started from.\n\nThe second possibility is that the Universe is flat. This kind of Universe can be imagined by cutting out a piece of a baloon material and stretching it with your hands. The surface of the material is flat and not curved. You can expand and contract it by tugging on either end. Flat Universes are infinite in extent and have no boundaries.\n\nFinally, the Universe might be "open" or have negative curvature. Such Universes are also infinite in spatial extent and have no boundaries.\n\nThus whatever be the shape of the Universe, there is nothing called a boundary and hence nothing called the edge or end of the Universe.
111534
Sorry dude, but I only have about 67% of the universe in my pocket. The rest I have no explanation for it's location.
632346
What is beyond the borders of the universe?\nIs it truly possible for the universe to go on forever? If there is an end, what’s on the other side?\n \nBefore we can address these questions, we must first define universe.  The word universe denotes all space and everything (matter, energy) contained within it.  The prefix uni means one.  The root verse means word, turn, or whole.  Thus our universe has traditionally been thought to be the one whole of all substance or matter.  Questions regarding our universe persist today.  Does it have a beginning and end, or does it go on forever and ever?  Is it linear or curved?  If it has limits of length or curvature, then what lies beyond the Universe?  If something lies beyond the Universe, then can’t we accurately call that the Universe?\n\nSome lay people and some scientists conceive of the universe as infinite space.  Others define the universe as finite, or limited (perhaps curved), space.  Still others incorporate the elements of matter and/or energy into their definition of the universe, as opposed to the space beyond matter and energy.\n\nGiven these concepts of our universe, some scientists conclude that the “totality of space could be infinite. Shrink an infinite space by an arbitrary amount, and it is still infinite. (Scientific American March 2005).”  \n\nAs to the notion that we live in an ever expanding universe, moving away from every other universe on the fabric of space-time, some scientists are careful to point out that “Andromeda, our nearest large galactic neighbor, is actually moving toward us, not away. Such exceptions arise because Hubble's law describes only the average behavior of galaxies (Scientific American March 2005).”\n\nIn accordance with your supposition that our universe is in another universe, “it has been hypothesized by some scientists that the universe may be part of a system of many other universes, known as the multiverse (http://en.wikipedia.org/wiki/Universe).” Modern astrophysicists talk about multiple "pocket" universes that branch off from one another.  Stephen Hawking points out that parallel pocket universes can have no effect on a real observer inside a single pocket, so, according to Hawking, they are theoretical baggage that should be eliminated from cosmology, the study of the origins of the universe.\n\nSome string theories define the universe as a three-dimensional space in an invisible space having more dimensions. This is, in essence, a universe within a universe.  Our zone, a “braneworld” could periodically bounce into another parallel braneworld.  This may create what would appear as a Big Bang from one perspective or a Big Bounce of alternating expanding and contracting universe from another perspective.  Such a cataclysmic event is thought to occur 300 billion years from now, resulting in the rearranging and creation of a new universe.\n\nBeyond the borders of the universe, there are other universes moving through a multiverse.  While scientists do not commonly believe that our universe goes on for an unlimited distance, despite its present expansion, they allow for the possibility that the multiverse may go on forever.  If there is an end to our universe, what’s on the other side is called the multiverse.  If there is an end to the multiverse, another term may need to be coined to describe what lay people commonly refer to as infinite space.\n\nSteve\n:-D
246450
It does contradict Einstein's notions of locality. Yet laboratory experiments have demonstrated the non-locality of particle entanglement. The philosophical implication is that another dimension, call it hyperspace, transcends ordinary space. The universe is a single hyperparticle.
70961
If the universe is infinite, it doesn't mean that everywhere is the center, it means that it has no center. Or, if you mean relative to the existing matter...well, that isn't infinite, and has a defined center.
584779
Which is the end of expanding universe? If any end exists, what will be behind this end?\n\nBefore we can address that question, we must first define universe.  \n\nThe word universe denotes all space and everything (matter, energy) contained within it.  The prefix uni means one.  The root verse means word, carnate message, meaningful substance, matter.  Questions regarding our universe persist today.  Does it have a beginning and end, or does it go on forever and ever?  Is it linear or curved?  If it has limits of length or curvature, then what lies beyond the Universe?  If something lies beyond the Universe, then can’t we accurately call that the Universe?\n\nSome lay people and some scientists conceive of the universe as infinite space.  Others define the universe as finite, or limited (perhaps curved), space.  Still others incorporate the elements of matter and/or energy into their definition of the universe, as opposed to the space beyond matter and energy.\n\nGiven these concepts of our universe, some scientists conclude that the “totality of space could be infinite. Shrink an infinite space by an arbitrary amount, and it is still infinite. (Scientific American March 2005).”  \n\nAs to the notion that we live in an ever expanding universe, moving away from every other universe on the fabric of space-time, some scientists are careful to point out that “\n\nAndromeda, our nearest large galactic neighbor, is actually moving toward us, not away. Such exceptions arise because Hubble's law describes only the average behavior of galaxies (Scientific American March 2005).”\n\nIn accordance with your supposition that our universe is in another universe, “it has been hypothesized by some scientists that the universe may be part of a system of many other universes, known as the multiverse (http://en.wikipedia.org/wiki/Universe).” Modern astrophysicists talk about multiple "pocket" universes that branch off from one another.  Stephen Hawking points out that parallel pocket universes can have no effect on a real observer inside a single pocket, so, according to Hawking, they are theoretical baggage that should be eliminated from cosmology, the study of the origins of the universe.\n\nSome string theories define the universe as a three-dimensional space in an invisible space having more dimensions. This is, in essence, a universe within a universe.  Our zone, a “braneworld” could periodically bounce into another parallel braneworld.  \n\nThis may create what would appear as a Big Bang from one perspective or a Big Bounce of alternating expanding and contracting universe from another perspective.  Such a cataclysmic event is thought to occur 300 billion years from now, resulting in the rearranging and creation of a new universe.\n\nWhich is the end of expanding universe? That may be determined in 300 billion years, when it stops expanding (like a balloon).  If any end exists, what will be behind this end?  A multiverse void containing other expanding and contracting balloons, referred to as universes, may exist beyond our own.\n\nSteve\n:-D
613729
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.
133475
The most recent investigations (WMAP) about the shape (geometry) of our universe show that it is FLAT, meaning that it will expand infinitely, parallel lines never meet, etc.,.\n\nhttp://map.gsfc.nasa.gov/m_mm/mr_content.html
31656
Um...\n\nWould it happen to be cosmic?
142254
Once you leave the Milky Way you are not outside the universe. The Milky Way Galaxy is one of many known galaxies in the universe. There are probably billions we don't know about. "Goodness knows where" is inter-galactic space.\n\nInfinity means "forever". It is not necessarily a measurable distance or time. We're not sure if the whole universe is infinite. We can't even see most of what is out there. The estimated size of the observable universe is 7.4x10^26m (that's really, really, really, really big). Beyond that we're not sure yet.