black hole / begining of the universe?
918848
According to general relativity, the matter inside a black hole collapses to a single point: a "singularity".  At this point, the mass density (ρ = m/V) is undefined (because the volume of a single point is zero). \nWe have a lot to learn about extreme cases such as this.
224610
unless this is a "zen" question, it doesn't "go" anywhere.  A black hole is a former star that has died and collapsed in upon itself and had its mass "infinitely" compressed into a tiny tiny volume.
616352
I find the concept of an event horizon with a singularity behind it where spacetime curvature becomes infinite fascinating. The idea of spaghettification is intriguing (and a bit frightening!) too. And although scientists reassure us that artificial black holes would be perfectly safe, creating one seems...well, crazy. On the whole, however, I find the whole concept fascinating and wish I had time to take an advanced physics or astronomy class to learn more about it.\n\nI'm afraid I don't understand the other commentator's God reference, though. What black holes have to do with God, or at least the Christian God, is completely beyond me. Last time I checked, the Bible said nothing whatsoever about them.
722109
It is possible that black holes are the catalyst behind the big crunch, which is the end version of the big bang. Once all of the black holes in existence collect enough matter and energy, they could combine gravitationaly to create one massive black hole that simply repeats the big bang over and over.\n\nBlack holes do not reflect anything, so I don't believe the ignition of the sun was caused by a black hole. \nBlack Hole Info:\n1.They represent matter/energy in its purest form. (All matter and energy is coalesced into one single state of energy)\n\n2.They represent the possible end of our universe.(big crunch)\n\n3.They are the single largest gravitational entity theorized to exist.\n\n4.They are one of the few places that prohibit the propagation of light, so no reflection.\n\n5.The laws of nature at a black hole are completely different from anywhere else in the universe.
515815
According to the standard theory, our universe sprang into existence as "singularity" around 13.7 billion years ago. What is a "singularity" and where does it come from? Well, to be honest, we don't know for sure. Singularities are zones which defy our current understanding of physics. They are thought to exist at the core of "black holes." Black holes are areas of intense gravitational pressure. The pressure is thought to be so intense that finite matter is actually squished into infinite density (a mathematical concept which truly boggles the mind). These zones of infinite density are called "singularities." Our universe is thought to have begun as an infinitesimally small, infinitely hot, infinitely dense, something - a singularity. Where did it come from? We don't know. Why did it appear? We don't know. \n\nAfter its initial appearance, it apparently inflated (the "Big Bang"), expanded and cooled, going from very, very small and very, very hot, to the size and temperature of our current universe. It continues to expand and cool to this day and we are inside of it: incredible creatures living on a unique planet, circling a beautiful star clustered together with several hundred billion other stars in a galaxy soaring through the cosmos, all of which is inside of an expanding universe that began as an infinitesimal singularity which appeared out of nowhere for reasons unknown. This is the Big Bang theory.
943441
Hey, I'm gonna give you the truth instead of spilling abunch of theories at you. \n\nNobody knows. Black holes and everything related to them are one of the most mysterious things out there. Not that we REALLY know much else about whats going on out there. Everything so far is based on theories drawn from basic laws of physics. \n\nWho knows, maybe you and I will live to see the day they can tell us it is a fact. I hope so, there are many questions I would like to know the answers to. =)\n\nEDIT: Bill, I believe the theory I last heard on that is as follows: \n\nOnce a black hole has nothing else to 'feed' on it will collapse. Scientist recently believed that the end of the universe was gonna be in a black hole, a super massive black hole, that was thought to be in the location of where the Big Bang took place. They assumed that the universe would quit expanding and retract on itself. They recently found out that they were COMPLETELY wrong in that assumption. In fact, the universe is expanding at a faster rate then it originally was. Their new theory is that the universe will continue to expand, eventually breaking down everything in the universe (sun, moons, and planets encluded). True? Couldn't tell you honestly, they may come up with a different theory tomorrow.
1014072
Forever doesn't have a start, that's partly what the word means. If the universe has a beginning, we don't how it began or what was there beforehand, there are only theories. The universe as we know it has been estimated to be at least 15 billion years old but, no more than 20 billion years old. (Different websites have different numbers though)
651133
The black hole is where the force of gravity has successfully joined our known universe back with infinitely dimensional space. \n\nSpace is where our universe was born in a disturbance known as the big bang.  \n\nThe black hole is the grand finale to gravity, gravity's 'goal' creating a porthole to where we came from before the big bang.  \n\nGravity is the connection space has with our universe, too stubborn to let us go and will one day bring us back to become nothing and everything with it once again.\n\nPeace Out
604912
These astronomical questions require astronomical answers. How to start and how to end?\n\nFact is, our existence is only a very very very very.......... small portion of time to calculate. To find how old, we have yet to discover evidence mainly because we cannot reach outside our very own galaxy to explore. Considering that it will take lightyears to travel the enormosity of time and space boggles all that best is people to come with a reasonable reason that will be hard to disprove. No one can. All can theorise.\n\nSo the universe is so large, it is beyond our perception, beyond our present ability to fully comprehend, and though we are making small progresses with probes and telescopes, it is still too huge and complex to grasp. We can theorise based on understanding of our surrounding and equating everything else to what we know. This is our limitation. \n\nUniverse has been around even before our gaalxy is formed bbillion zillions years ago. The acceptable theory is that a big bang ceated our galaxy and out solar system. Something must happen, and people theorise it must be sudden, that is why the bang. And it just happen like that that our galaxy was formed, and then our solar system. No one can track back and so this is so. Hence, theory is what we can do to try to explain to ourselves.\n\nSupernova is a dying star, giving its last burst of energy befre collapsing. Death of stars is something little understood because it is rare. Stars take million of light years to reach us and so we are watching history when some event occurs. So far, only a few supernova had been documented. And these stars actually died millions years beforehand.\n\nIt is theorised that when a star dies, it collapse into itself, as stars are suppose to be like our sun, all gaseous. It is theorise that the star will collapse into a very dense body with very high gravitational pull that it sucks everything nearby into itself. This is the black hole.. It is theorise that it will be so dense that even light cannot escape. So far possible sighting of black hole has been done by noting the bending of light in the universe, since the black hole cannot be seen \n\nSo, outside our atmosphere, we have theories to try to explain everything we see. We need a reason to justify the things we see in space, rather than accepting that they are there even way before life begins on earth, and that there will be many flawed theories because at this time, it is just beyong our ability to check it out.
989306
A very good question but one that we don't know the answer to yet.  It is a hypothetical situation that could create a wormhole or perhaps the center of a blackhole is where this kind of phenomenon occurs.  The bottom line is that there is no hard evidence of this but it seems possible according to mathematical models.
122538
Currently the universe is expanding. However, we are not sure yet whats going to happen in the future. This is because it is possible that the universe will constantly keep on expanding as it is right now. Or it is also possible that the gravitational pull of the universe will be so huge that it will collapse under its own gravity. Right now, we are almost at a point of intersection between these 2 cases and in a few thousand years we'll know exactly where this is going. Ofcourse, you and I wont be around to witness that, but astronomically its a small amount time.
502704
The universe is believed to have begun with the Big Bang. However the term 'begun' is a bit misleading since the Big Bang created time itself. Thus, if you think about it, the universe began with the Big Bang but, at the same time, it was always there since time itself only started then!\n\nIF the universe is on course to collapse in the Big Crunch presumably the argument will reverse and time will come to an end.
989936
Curved spacetime.\n\nThere is nothing unduly special about the event horizon (ie it has no discontinuities). And very large black holes do not have unduly curved spacetime at their event horizons (the curvature of the supermassive black hole at the centre of our galaxy is on 20 times greater than that here on Earth, and here on Earth the curvature is pretty much undetectable).
514185
does the universe end?  no one knows yet.  the beginning of the universe is much better understood.\n\nhttp://en.wikipedia.org/wiki/Ultimate_fate_of_the_universe
524567
First of all, the Big Bang theory does not address how the universe actually got started. It describes how the universe has been since that point. And it is remarkably well established for times after about 1 millisecond after things got started. The universe is expanding and went through a period of very fast expansion early on. The temperature has been decreasing since the start which was about 13.7 billion years ago.\n\nHow things actually got started is *much* more specualtive. There are two main ways that people approach this, but I want to emphasize that neither is actually part of the Big Bang theory and that both are *very* specualtive. We simply don't have the data to figure out what happened before that first millisecond or so.\n\nThe first approach is to point out that time itself is part of the fabric of the universe. It is not something idependent. Part of the nature of the Big Bang in general relativity is that it is a 'singularity'. An analagous thing would be to look at the north pole. This is a singularity in the coordinate system of latitude and longitude. You can't go 'north of the north pole'. In a very similar way, the time coordinate cannot be extended (in this approach) past the Big Bang. This means there is no 'before the Big Bang'. Time simply doesn't make sense at that point.\n\nThe other main approach is to say that the singularity predicted by general relativity doesn't happen because of smoothing out by quantum effects. This *could* allow the time coordinate to extend past the Big Bang (but it doesn't have to). In this scenario, the Big Bang was a quantum fluctuation that 'got out of hand' and underwent exponential growth becoming the universe. The beginning was random since such quantum events are random (this is known and established). However, there would be physical laws describing the probabilities of such things happening. In this approach, there can be multiple universes that don't interact and that have various physical properties different than our own.\n\nI hope this helps!
253987
I can't say i'm a supporter of either UNS / BigB theories coz both isn't convincing enough to me. Your point here is exactly why i don't believe in UNS, as for BigB, yes your argument does suggest that everything starts from a singularity.. then what is that singularity? Can universe be considered started because of the big bang then? or was that singularity was actually been part of the universe all along? if you think from here further.. don't you think UNS sounds more logical?\n\nall and all.. they're all theories, and believes.. just like we can't prove the theories about Multiverse.
209863
according to a theory of big bang, there is a black hole at the centre of our galaxy that exerts such a huge pull of gravitatinal force on things towards it that even light  pulled towards it never traces back or is never reflected agin. isn't that amazing!