how can the universe be extending if it's infinite? Is the universe infinite?
448565
I think no one could truthfully answer that, as nobody knows knows the universes limitations..
38951
The universe has no center, but it is not infinite.  It is finite but unbounded, like the surface of a golf ball.  The surface does not have a center nor a boundary, but it is not infinite.
1094356
It means that we can measure the size of the universe, but if you tried to approach an "edge" of the universe, all you would do would be to extend it. Wherever you go, the universe goes with you, so it is unbounded. You cannot go "outside" the universe.
410246
Well, this is uncertain. I will explain it as it is currently understood. There are three possibilities based on relativity and the Standard Model. There are three types of expansion depending on the mass-energy density of the universe - open, flat and closed.\n\nIn an open universe, expansion will continue and will actually increase with time. This is because there is not enough mass and energy in the universe to pull it back in.\n\nIn a flat universe, the universe will continue to expand, but expansion will begin to slow at a certain point and as time approaches infinity the expansion will stop. Of course, since infinity means forever, the expansion will continue but slow down constantly, little by little.\n\nIn a closed universe, there is enough mass and energy to cause a collapse of the universe, known as the "big crunch."\n\nAnyway, current theory holds that we live in a flat universe and that inflation will continue forever, as mentioned.\n\nOh. It expands into nothing - as in before the universe is there, there is nothing there.
9649
It does not end and its growing, before you try tackling such a question, answer the micro-level questions of the same kind.  The universe encompasses all that exists, and by default then, it is largely unknown.  We don't know where the universe ends, and all evidence points to it being endless and growing, therefore we make a conclusion based on a portion of the information actually needed.
680741
Well we couldnt go to the end.. because time is what results from the universe expanding.. so as time goes on.. the universe keeps growing
265923
Yes. The universe is constantly expanding. It is possible we are all being sucked into a massive black hole, far far outside the reaches of our universe which would account for the the expansion of our universe. Additionally, the best competing theory for the start of the universe is the big bang , where everything expands out of one tiny point. It is reasonable to think that the universe could end in the opposite way - The Big Suck, where we get pulled into a massive black hole, just like the one you describe. So yes, I think it's very possible.
784741
The universe may be infinite in size, or it may be of only finite size. Doesn't the universe have to be infinite? It doesn't make any sense that it would be finite, then there would be some end or edge, and what would be beyond that?\n\nStrange as it may seem, the universe could be finite, a finite universe would not have to have any edges or an end, it could 'wraparound'. The universe could be curved. Huh? How could you curve the universe?\n\nAn analogy should help, consider the surface of the Earth. It looks flat and many children and ancient people might assume that it is flat and that it is either infinite or must have an end or edge somewhere.\n\nBut the Earth's surface is curved, it wraps around and closes in on itself. There is only a finite amount of area yet there is no ends or edges. The two-dimensional flat surface of the Earth is wrapped around into a sphere when viewed in three dimensions. If you set out flying westward in a plane, you will wraparound and eventually return to where you started, approaching from the east.\n\nThe universe may be a curved three-dimensional space that wraps around and closes on itself. If you set out in a spacecraft heading one direction, you could eventually return to the same spot from the opposite direction.\n\n \n\nA nice demonstration of the scale of the universe is to start with a view showing our galaxy and then zoom by a factor of ten once per second. Such a demonstration is done at http://micro.magnet.fsu.edu/primer/java/scienceopticsu/powersof10/ \n\nClick on this link and view the demo. Use your browser's Back button to return to this page after watching the demo.\n\n\nThe entire universe, or just the visible portion of the universe if its infinite, is roughly 27 billion light-years across. That's 159,000,000,000,000,000,000,000 miles. Our solar system, from the Sun to Pluto, is .00063 light-years across or 3,720,000,000 miles. That makes our solar system 42,700,000,000,000 times smaller than the whole universe.\n\nCan we put that into a more meaningful perspective? If the entire Earth's surface represents the whole universe, the solar system on that scale would be one-millionth of a meter wide, about 1/25,000 of an inch, the size of a single, small bacteria.
33684
The Universe is boundless, yet finite.  So you could never exit the Universe.
300537
There is disagreement over whether the universe is indeed finite or infinite in spatial extent and volume. Many astronomers and cosmologists believe the universe is infinite due to recent findings in NASA's WMAP project supporting a flat (therefore infinite) universe\n\nHowever, the observable universe, consisting of all locations that could have affected us since the Big Bang given the finite speed of light, is certainly finite. The edge of the cosmic light horizon is 13.7 billion light years (4.19 Gpc) distant. The present distance (comoving distance) to the edge of the observable universe is larger, due to the ever increasing rate at which the universe has been expanding; it is estimated to be about 78 billion light years (7.8 × 1010 light years, or 7.4 × 1026 m). This would make the comoving volume, of the known universe, equal to 1.9 × 1033 cubic light years (assuming this region is perfectly spherical). The observable universe contains about 7 × 1022 stars, organized in about 100 billion galaxies, which themselves form clusters and superclusters. The number of galaxies may be even larger, based on the Hubble Deep Field observed with the Hubble Space Telescope. The Hubble Space Telescope discovered galaxies such as Abell 1835 IR1916, which are over 13 billion light years from Earth.\n\nBoth popular and professional research articles in cosmology often use the term "universe" when they really mean "observable universe". This is because unobservable physical phenomena are scientifically irrelevant; that is, they cannot affect any events that we can perceive.
116835
Here's the flaw in your logic. You think that the universe has to be in something else to expand. The Universe is literally being created more and more. By this I mean the volume of real estate in reality is growing. There doesn't have to be something else that it's growing within. It sets it's own barriers and those barriers mark the current circumference of existence.\nBy the way, science does not respect theories. It respects laws.
626822
The Universe is expanding, but it doesn't have a phyiscal start, middle, or an end.  It's going to expand forever. Don't think about it, because it's not something our mind can really grasp.\n\nHere's an analogy that helped me:\n\nImagine the Universe as a two dimensional place.  The Universe is the surface of a rubber ball.  There's no start, finish, or middle.  As the Universe expands, the rubber ball fills with air.  Still no start, finish, or middle.\n\nFor a long time, it was unknown whether the Universe was open or closed, meaning whether the Universe would expand forever or eventually collapse back on itself back to nothing.\n\nThe hubble telescope proved that the Universe it open and would expand forever.
178670
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.
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.
1163982
This answer is in responce to gimpalomg, and all other  "athiests."  If the universe were static, we could not say it had a beginning, and could have been eternal. However, the fact that the universe is expanding and going to higher and higher entropy, we can "turn back the clock" and determine that it in fact had a beginning. This is not the case with a deity. It CAN be static, everlasting, eternal. It is only that we do not understand the full measure of what "eternal" means. We as finite beings only think in finite terms, even when talking about infinity. We say it is "a really, really big number that goes on forever". But that's just semantics. We really have no conception of eternal and everlasting. \n\nPeople say we can not prove God exists, therefore he doesn't. What gives us the audacity to think we should be able to prove that? We can only know what he has communicated to us.
429398
Well, think this, the universe is infinite. Wouldn't be kind of ridiculous to think we are the only smart ones around in such an endless space?
689891
it's called infinite.\nIt never began and it will never end it always has been and since it was thought up by man it's infinitivity can't be described because it's not there to the universe bu only to us since everything to us has a begining and an end but the universe will always be. this may sound onfusing but that's because the thought of infinity and the universe and time is only slightly comprehendable to the human minde, anything past 9 planets, 1 sun and space is just...confusing!