Why do some scientist believe that the Universe is expanding?
465735
The Universe is Expanding because it has been observed that the galaxies within the Universe are moving away from us at tremendouse speeds. The Doppler Effect explains the red shift observed through hundreds of telescopes which confirms the fact that the galaxies are moving away from us. If the Universe were not expanding, then the Galaxies would not be all moving away from us, but moving with us. The more perplexing question is if the Universe is expanding, then it is expanding into what?
417751
Mixing ideas of Science with the notion of God is rather funny. Do you believe in some heavenly creature? If yes, it was created right at the moment when you started to believe in it.  \n\nMoreover, are you sure that science considers time and space to have no start or end? If our universe is expanding with the speed of light, then what lies out of its expanding borders? Nothing, not just cosmic vacuum. Simply nothing.
168520
I believe that the universe is expanding within higher dimensional space. As humans we can only understand this universe in three dimensions because that is all our primitive tools of perception will allow. We are "trapped" in three dimensions. However, the existence of higher dimensions has been proven mathematically time and time again. I'm no expert on the subject but I have done a little reading. I would reccomend reading something by Stephen Hawking such as "Stephen Hawking's Universe" or "A Brief History of Time." Also, "Hyperspace" by Michio Kaku gets a little more in depth with higher dimensional theories. The only way we can understand an expanding universe is through expanding our minds along with it.
804251
The Big Bang theory does have a good amount of evidence behind it. So we’ll take a look at the three biggies.\n\na) Cosmological Redshift: We can use spectroscopy to determine the rate at which galaxies are moving away from us. Additionally, since it takes light time to travel, the further away we look, the further back in time we are looking.\n\nWhat we find, is that all galaxies in the universe are moving away from us. The further they are, the faster they’re moving away. So if we play the whole thing in reverse, all the galaxies will come back together at a single point in time. This point in time is what we call the Big Bang.\n\nb) The Cosmic Microwave Background (CMB): Figuring that if you played everything back in time like this that all that energy would be crammed into a smaller space, that means the temperature would go up. And also since galaxies couldn’t have formed yet, we’d expect a gaseous sort of universe early on. As I discussed earlier, hot dense gasses emit photons at a peak wavelength corresponding to their temperature. Unfortunately, since things were so dense, photons couldn’t get very far.\n\nHowever, with the available information, astronomers were able to determine at what density and time, photons would finally be able to get far enough that we could observe them. This is called the “surface of last scattering” and has a very specific temperature. So we should be able to look for photons with energy (wavelength) corresponding to that temperature.\n\nBut due to redshift, they will appear at a different wavelength. This radiation should appear from every direction. This was a prediction made by the Big Bang theory that was later confirmed by Penzias and Wilson who stumbled on it accidentally!\n\nNo other theory of the universe has ever been able to make such a profound prediction to the degree of accuracy the Big Bang did in this instance. Making such amazing predictions is one of the highlights of a good theory. None before or since have ever been able to pull off such a feat.\n\nBut the successes of the CMB prediction don’t stop there. Another important piece of the puzzle lies in that the CMB couldn’t be completely even. If it were, then galaxies couldn’t form since there would be no “seeds” with higher mass and thus a stronger gravitational pull to form around.\n\nThus, the Big Bang theory had to predict that the CMB would not be completely homogeneous. It should have some variations to it, and those variations would have to be of a specific size in order to get the universe we see today.\n\nEarly results for the Big Bang didn’t look too good for this prediction and threatened to sink the whole ship. However, the devices used were not actually sensitive enough to pick up these minute variations. But recently, with the Wilkinson Microwave Anisotropy Probe (WMAP), these perturbations have been discovered precisely as predicted.\n\nScore two strong predictions for the Big Bang. Zero for any others.\n\nc) Distribution of Elements: With the conceptual framework intact thanks to the first point, it was also possible to calculate how much of each element should be formed in the initial event. It should be obvious that, given a bunch of protons, electrons, and neutrons, hydrogen should be the easiest to form. Indeed, stick a proton and an electron in a room together and they’ll automatically hook up due to their magnetic attractions.\n\nAdditionally, with such high energies, it would be possible to fuse some of this hydrogen into helium and even a little bit of heavier elements. Since astronomers had a good handle on the energies, it was possible to calculate how much of each there should be. If that number didn’t match up with observations, the Big Bang theory would be shot.\n\nFortunately, the predictions do match up pretty closely. I stated a value earlier of 80% hydrogen, 20% helium, and neglected the rest since it would be statistically insignificant. In the universe today,
334992
There are thoeries but they are just that theories.  Some people believe in the big crunch, in that the universe will eventually stop expanding and then retract to a singularity.\nOr that black holes will carry on being created and absorb one another untill the entire universe is swallowed up.\n\nBut to be honest science does not really have the means to provide a definitive answer at the moment.  We will have to wait and see.
73345
The last response made a good point.  Science only seeks to answer certain questions.  What exists "outside" the universe? What existed before the Big Bang?  These are questions that scientists currently are not seeking.  That question is left up to the philosophers for now.  \n\nThe questions really point to a better understand of the universe and whether that question is important, relevant or even consistent with our present knowledge of the universe.  \n\nAstronomers and physicists find the surface of an expanding balloon a good analogy for the nature of our universe.  The surface, just surface mind you, of that balloon has no center or edge to it.  Just like how we understand the universe.  The surface material of the balloon would be what we call space-time.  \n\nWhat is outside the surface of the balloon?  Well there is no balloon material outside so it is not space as we know it but one perspective says it is a future balloon surface.  Just like inside the balloon was once a past balloon surface.  \n\nThe universe could have a similar analogy.
210647
What lies beyond the edge of the universe is matter that is receding at a speed greater than that of light relative to us. Check out the Begy atomic model, It proposes that the big bang has no beggining and no end and is an ongoing process. Belief in God is possible, comprehension of God is not.
5808
Nobody really knows for sure.\n\nThere's a theory that the universe is expanding in a spherical shape and will continue to expand until it reaches maximum entropy. At that point all of the energy and matter in the universe will be equally distributed and the universe will no longer be able to support life.\n\nThere's another theory that the universe will expand (again, roughly in the shape of a sphere) until all of the galaxies exhaust their kinetic energy. At that point the universe will begin contracting. When the contracting is complete a singularity containing all of the mass in the universe will form and explode in a big bang.\n\nIf you think about it, if the latter theory is true then it's possible that the universe has expanded and collapsed an infinite number of times in the past!
297935
Big Bang is a theory that tries to explain the formation of the universe, its galaxies, its stars and planets etc.\n\nIt says that the Universe was created by an explosion of a Primeval Atom thus causing it to expand and move away from each other. This was actually based on the Hubble Law which says that Galaxies around us are expanding at speeds directly proportional to their distance from Earth, based on the observation of Edwin Hubble, 1929.\n\nIts a huge topic with lots of technical arguments and counter arguments. Here is the link that will satisfy your quest on Big Bang, atleast for starters...\n\n.:Fishie:.
176516
This is an issue of science not religion. Science makes predictions based on observation, and if they come out right the theory is adopted. Based on Edwin Hubble's observations on the spectrum of faraway stars, where certain elements' lines were shifting to red along the time, the conclusion was withdrawn that they were increasing their distance from us, in all directions, therefore, the universe is expanding. Given the rate of expansion it was figured out that between 13 and 15 billion years ago all matter must have been clumped together. recent observations with anisotrophy probes showed that the background radiation of the cosmos dates back from 13.7 billion years. So at that time all matter/energy was clumped together and what we call a quantumn fluctuation set it in expansion. All matter was formed within a trillionth of a second followed by a quick expansion. This is proven by physics by means of mathematical equations that for the common mortal are just beyond mental reach, but fortunately some humans developed a very intelligent brain. Unless of course you prefer to think that a pink unicorn sneezed, and there you got the universe. In which case, be my guest, but deep down inside I'd pity you. (But in fact I know you don't believe such fanciful stories).
967928
You know something, you are very uninformed. For you information:\n\nMost scientists believe in some sort of creator or deity. There is a simple explanation for this, and that is science can incorporate the idea of the supernatural since there are places that science cannot go.\n\nThe creation of the universe is one of them. Science can explain all the way back to 10^-43 seconds, but before that there is no explanation, there is only the unknown that is just as well explained as God as any other theory. So God and science are not at odds here, as Albert Einstein and Stephen Hawking would agree\n\nSpeaking of my great, great, uncle, several times removed Albert Einstein, he is quoted as saying "God does not play dice with the universe." What he meant by this was a repudiation of Heisenberg's Uncertainty Principle, because to Albert the universe was a beautifully ordered and created place, created by God.\n\nSome scientist see God in randomness (Heisenberg). Others see it in harmonies of patterns and chaos (Glick and Mandelbrot). Even Darwin still credited God for creating the universe, though he sought scientific explanations for the evolution of species.\n\nThese men were/are fervent men with fervent beliefs. The fact that they deal in science in no way impedes their beliefs in God.\n\nNow, that being said, what you believe God did or does may not be the same thing that these men believe, maybe because they understand Gods universe better, maybe because they are more open minded than to narrow their vision to a few hundred pages of a book, a book that is interpreted many different ways so that who knows which version is right, if any. But when it comes down to it, they believe in God in one form or another, and maybe their views are more enlightened than most.\n\nYou can count me with them, by the way, as I take a more scientific view of the world. I am Deist, what that means is I believe in God as a first cause. I believe that God set the beautifully intricate stage, that we are still trying to understand, and let it be, to run the way it will, a universe of detail ever unfolding.\n\nBTW I gave you a thumbs up on the question, because while it was indelicate, it was thought provoking and deserved an answer, even if it was mostly my opinion.
1137754
I believe it. I also believe in the theory, in which, as you may also know, whole cosmos is going to turn back into that extra atom. What I wonder alot, when the expansion of the universe will stop and start to shrink back :=)))
862094
The space between the galaxies is what is expanding.  Imagine raisin bread being baked.  As the bread rises, each raisin moves away from every other raisin.  Another way to visualize this is by drawing dots on a balloon then blowing the balloon up.  As the balloon get's bigger, each dot moves further away from every other dot.  It's the same for galaxies.\n\nNow the expansion of the universe is only detectable at extremely large distances.  Nearby galaxies like M31 can move towards us.  But most galaxies we see are extremely far away, so almost all of them are receding from us.
1059228
If the universe is everything, then what is it expanding into?\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.  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\nIf the universe is everything, then what is it expanding into?  It seems that our universe is all matter, space, and energy that we can perceive in this closed system.  However, that does not mean that there is not additional matter, space, and energy outside our universe.  In other words, there are probably other universes.  Therefore, the zone that we call our universe (or braneworld) may be moving through or expanding into other universes (or braneworlds).  In sum, all universes may be moving through a multiverse.\n \nSteve\n:-D
1149831
So far our observations are leaning more towards open, because our universe is expanding at an accellerating rate, and it shows no sign of slowing, if it were closed (which we havent found enough matter in the universe to help this theory) then the expansion would slow, come to a stop, and come back and collapse back in on itself. But so far evidence is telling us it won't.
574337
There are various conflicting theories about this.Some say universe will keep on expanding.Some say it will be a see saw .Some say it will all end in a big contraction.It's still a open question.
1099710
You are thinking 3 dimensionally. There is no center to the universe in 3 dimensions even though it IS expanding...