If everything goes to infinite in sigularity, why does a blackhole have a finite mass?
353330
Everything does not go to infinity in a singularity, only a few things do....some things go to zero.\n\nA black hole's mass is constant, it has the same mass as the material that formed it.\nA black hole's volume, or rather, the volume of its singularity is zero.\nIf the black hole has some finite mass but no volume, its density (D = m / v) goes to infinity.\n\nThe time dilation experienced at the event horizon of a black hole is infinite as well.
943076
You can spin a black hole?   Well aren't you talented...  actually the whole known physical universe is first and foremost a gigantic black hole, and it is in motion.  Before the first star formed the dark spacial universe existed and on the smallest scale there is no empty space, everything is connected.  It has been said that darkness is merely the absence of light, but there's no such thing as nothing, everything is made of something, even the ordinary everyday nighttime darkness, on some immeasurable scale even your shadow is made of something?  Black holes are a different more massive type of darkness comprised of dark physical matter.   There's a theory that every galaxy has one at the center and without it the stars that form a galaxy couldn't exist, and it's probable that it is already spinning, nothing is actually sitting still.  It's estimated the output of light from all the stars should be enough to light up the whole universe, but it doesn't.  Then where does it go, what happens to it, we know on a sub atomic scale it doesn't simply dissipate?  Where does the darkness go when you switch on a light?  When you turn off the light, obviously it's still there, so wasn't it there the whole time?   Well, there are still more questions than answers, and maybe you should be a physicist, perhaps you could find an answer to the enigmas of the infinite machine.
1132943
a black hole is an infinitely dense point, called a singularity
880821
This is an odd question because we are treating ininity like a number. Half of something going to infinity is still going to infinity. There are ways to count different infinities -- there are countable and uncountable ones -- but dividing by 2 does not make a difference.\n\nMy advice is ignore the half infinity for this reason and treat it as a particle in free space. This is common answer which can be found in all text books. The way to approach is take a finite square well and find the condition as we increase the boundries to infinity. They will be the same answer -- namely a free particle in space.
580033
You've probably seen the pictures of a grid with a giant funnel extending infinitely downward.  That's not the shape of the hole itself, but a map of the curvature of space near the singularity.  The singularity, or "hole" itself is a point of infinitely large density and infinitely small size.
849237
There's most likely not an 'other side'.  A black hole is a bunch of matter that's been compressed down into a singularity, or an extremely dense spot.  More stuff falling into the hole isn't going anywhere; it's just contributing to the density of the black hole itself.
349795
I don't think the Heisenberg uncertainty principle would apply here, but the related Pauli Exclusion Principle might tell you something about how the masses would combine. But I seem to recall that the whole idea of a black hole is that all known mechanisms of preventing continued collapse, including the Pauli Exclusion Principle, are overcome by gravity and so all the mass of the black hole occupies an infinitely small volume. However, the event horizon, which is the distance from the center at which the escape velocity is exactly the speed of light, would get bigger. But that calculation is a simple gravity problem and does not depend on quantum mechanics at all.
1095417
A black hole is a spacial anomalie with an extremely high gravitational mass, and supercondenses matter into an infinitismally small singular. If all the matter in the universe could be condensed into a ball the size of a speck of dust, then the size of the ball inside a black hole would be a fraction of a fraction of that, too small to see with the most powerful microscope on planet Earth. The hole however is much different, similar to a funnel. So at different points in the hole the size measurement is different. There is no actual hole however, more like a bend in the fabric of space, so nothing ever actually leave the universe, only changes density, form and location, among other things.
31855
Like the posters above have said, the known laws of physics break down inside a black hole. Anything which passes inside the event horizon is no longer visible to anyone outside. What happens inside is just pure speculation, take your pick:\n\na. Matter, light and other trapped energy is compressed to incredible density\n\nb. Everything breaks down into its ultimately basic constituents (quarks, strings, whatever).\n\nc. Everything passes through a 'worm hole' to a 'white hole' somewhere else in the universe or in a different universe. A white hole (no one has ever observed one) is the opposite of a black hole, where everything is emitted out. It would appear like an incredible sourc of light.\n\nd. Black holes accumulate matter and energy, and ultimately the whole universe is concentrated into one single black hole. Suddenly "Let there be light", and it all explodes in another Big Bang to form a new universe. This is also called the theory of oscillating universes.
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.
292835
According to Einstein's Theory of Relativity, E=MC squared, where E is energy, M is mass, and C is the speed of light, in order for something to approach C, it must have very little mass and a hell of a lot of energy.  However, if something has enough energy to approach the speed of light, its mass would be infinite. This means that even if you weigh 0.00000001 grams, which is basically nothing, when you approach the speed of light, the infinite energy that you have will make your mass infinite also (if you don't already burn up, that is)...you'll weigh more than everything in this universe combined.  You'll rip a hole through this universe like a heavy piece of weight through a thin piece of paper, then you'll be like a black hole sucking everything in.  However, since the energy in this universe is limited (and not infinite), if you somehow can harness ALL the energy in this universe to use for travelling, you'll only move as fast as the speed of light...that is, there's simply not enough energy in this whole universe to allow you to go faster than light by even .00001%, so we're basically "trapped" in this universe, unless we can find an alternate "exotic" energy source from another universe to use, or somehow "bend" space so that we can go from one point to another instantaneously. Now, photons are "light particles" that travels AT the speed of light, so they are the fastest things in this universe, so you may be wondering, "Well, since they travel as fast as light shouldn't they be very heavy also?"....and the answer is NO !!!   because although photons have the exact amount of available energy to travel as fast as light  (because they ARE light), they have absolutely zero mass....That's why when you shine a flashlight at your friend's forehead while he sleeps or something, you won't punch a hole through his head....because photons weigh NOTHING.
1003903
There are three possibilities, depending on solutions to the equations of General Relativity and how much mass is in the universe:\n\n1. the universe will stop expanding and then collapse in on itself to a big crunch\n2. the universe will keep expanding for ever\n3. the universe will reach a "stable size" - neither collapse nor expand forever\n\nNo-one knows which.
387898
Black holes are food for my brain and curiosity. I love the subject it is so interesting!\nBackround info: A black hole is a concentration of mass great enough that the force of gravity prevents anything from escaping from it except through quantum tunneling behavior. The gravitational field is so strong that the escape velocity near it exceeds the speed of light. This implies that nothing, not even light, can escape its gravity, hence the word "black." The term "black hole" is widespread, even though it does not refer to a hole in the usual sense, but rather a region of space from which nothing can return. Theoretically, black holes can have any size, from microscopic to near the size of the observable universe.\nBlack holes are predicted by general relativity. According to classical general relativity, neither matter nor information can flow from the interior of a black hole to an outside observer. For example, one cannot bring out any of its mass, or receive a reflection back by shining a light source such as a flashlight, or retrieve any information about the material that has entered the black hole. Quantum mechanical effects may allow matter and energy to radiate from black holes; however, it is thought that the nature of the radiation does not depend on what has fallen into the black hole in the past.\n\nThe existence of black holes in the universe is well supported by astronomical observation, particularly from studying supernovae and X-ray emissions from active galactic nuclei.\nMy answer 1)time travel when you, or in this case an object, goes fast the world goes slow. and if something, a black hole, is going, or sucking, fast enough, the world around you will eventually begin to reverse.
57542
Scientists think that, at some point in the very distant future, all of the mass in the universe will be dominated by four or five supermassive black holes.  At first glance, this doesn't square with the second law of thermodynamics (since that's a rather low entropy state), so someone postulated that there would be such a thing as a lighthole which would re-emit everything that fell into a black hole.\n\nThat was utter nonsense.\n\nStephen Hawking put his brain to work on this problem, and solved it in a day.  He realized that, as predicted by Einstein's famous equation, gravitational fields can spontaneously create pairs of particles (one being normal matter, and the other being anti-matter).  Under normal circumstances, the matter-anti-matter pair would annihilate, but if the pair forms on the event horizon of a black hole, one of the particles would be drawn into the black hole, while the other would be emitted into space.  By doing this, the black hole has expended some of its gravity, and therefore its mass.\n\nThe answer to the conundrum is that Black Holes are slowly evaporating through this process, and we've named it the Hawking radiation, accordingly.  If the Universe is ever dominated by a handful of supermassive black holes, that won't violate the Second Law of thermodynamics since they're slowly falling apart anyhow.\n\nThere is no need for a white hole to exist, nor is there any observational evidence even suggesting that they might.
273528
The defining factor of a black hole is that the escape velocity is higher than the speed of light.  This is a function of density and not total mass.  It's possible to have very small black holes.  They can even have masses smaller than that of an atom.  The LHC at CERN, which is expected to come online in 2007, may be capable of producing such microsingularities.  \n\nAs for our universe being a black hole...  from inside it's certainly not.  But, from "outside", if you can define such a thing, maybe it does appear as such, since light cannot escape out universe.  This assumes, however, that there is an outside from which this can be considered, and there's no proof, and perhaps no way to prove, whether or not there is.
190845
I believe there are two kinds of black holes. One I'm sure everyone will explain to ya, a great mass so large that light can't even escape it's gravity. But the other kind is theoretical: What if everything in THIS universe came from somewhere else? That is the only way I can explain it, except that somehow we are all headed for it again, to be sucked into it and expel ed into another place which right now is completely void, and this universe would be turned inside-out again.
38830
a black hole is a point of infinite density and gravitational pull. First of all you would be dead from different gravitational pulls from the black hole. Second of all, time from your perspective would stop, assuming that einstein is correct and your image would be spread out over an infinite period of time so your friend would see nothing.