Is there such things as black holes?
481008
Yes, they have gravitational pull strong enough to pull in light, but there is one known thing that can escape, thermal radiation. Steven Hawking's book a brief history of Time. There are many theories about black holes, but yes they exist.
1057606
Most people *don't* believe galaxies are black holes.  A black hole is a region of space from which nothing can escape, even light.  \n\nSince you can't see a black hole (that light that isn't escaping), one has to rely on indirect evidence.  \n\n If you've found a large mass concentrated in a small volume, and if the mass is dark, then it's a good guess that there's a black hole there.  \n\nIt'll be quite some time before we can get "hard evidence" of a black hole.  We don't even have "hard evidence" that those are stars; it's just indirect evidence.
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.
604401
blackholes exist.AND the second one,we have energy stored i ourselves in chemical form which we can convert into mechanical form ,like when we run or do any work the chemical energy that we had a part gets converted into mechanical energy.After death chemical energy is still present there with decaying a part of it is being lost to the surrounding thus with time the energy content will decrease.
823226
Um...  No and Yes?\n\nThe Universe has infinate volume.  Most of this volume is empty...\n\nA Black hole has no more gravity than the star and matter that has fallen into it, so never fear that everything is going to be pulled into a single super Singularity...\n\nAs to it eventually causing another "Big Bang"...  How do we know that a "Black Hole Singularity" is the "Big Bang Singularity" of another universe?\n\nBlack Hole Theory states that a Black Hole is so massive that it gives space infinite curvature...\n\nPresuming that the multi-dimensions discussed be the Super String Concepts exist...  \n\nThen how do we know that this infinate Curvature does not extend to an infinate volume of other spacial dimensions? \n\nOr rather...  Give thought to the possibility that a Black Hole Singularity is the "Big Bang Singularity", and that our entire universe of infinate space may exist in the Black Hole in another Universe that uses diferent spacial Dimensions...\n\nThere's no evidence either way...  So to answer you question which askes for definate answers that no one can give definately, let me say...\n\nProbably not but Maybe yes...  But Maybe yes but not really...  8-)\n\n"There is more to Heaven and Earth than is dreamt of in your philosophy Horatio"  -Shakespeare
375753
As far as I know, there are only 2 real-life examples of such a process: the Big Bang and a black hole.\n\nThe Big Bang caused 'everything' to expand into 'nothing'. That in itself is an infinitely large expansion; it's like dividing infinity by 1.\n\nA black hole is, in essence, where matter collapses to zero size, thus reaching infinite density and creating a hole in space-time. Little is known about the interior of such black holes, or, indeed, if there is such a concept.
696294
Not believed to max out as you say.  The diameter of the event horizon will keep expanding as new material is drawn in.  Stellar black holes are believed to be only a few miles across, while super-massive black holes comparable to the size of the solar system are believed to exist at the centers of some galaxies.
6001
yes!!\n\nBlack holes are predictions of Albert Einstein's theory of general relativity. In particular, they occur in the Schwarzschild metric, one of the earliest and simplest solutions to Einstein's equations, found by Karl Schwarzschild in 1915. This solution describes the curvature of spacetime in the vicinity of a static and spherically symmetric object, where the metric is\n\n    ds^2 = - c^2 &#92;left( 1 - {2Gm &#92;over c^2 r} &#92;right) dt^2 + &#92;left( 1 - {2Gm &#92;over c^2 r} &#92;right)^{-1} dr^2 + r^2 d&#92;Omega^2,\n\nwhere d&#92;Omega^2 = d&#92;theta^2 + &#92;sin^2&#92;theta&#92;; d&#92;phi^2 is a standard element of solid angle.\n\nAccording to Schwarzschild's solution, a gravitating object will collapse into a black hole if its radius is smaller than a characteristic distance, known as the Schwarzschild radius. Below this radius, spacetime is so strongly curved that any light ray emitted in this region, regardless of the direction in which it is emitted, will travel towards the center of the system. Because relativity forbids anything from travelling faster than light, anything below the Schwarzschild radius – including the constituent particles of the gravitating object – will collapse into the center. A gravitational singularity, a region of theoretically infinite density, forms at this point. Because not even light can escape from within the Schwarzschild radius, a classical black hole would truly appear black.\n\nThe Schwarzschild radius is given by\n\n    r_s = {2&#92;,Gm &#92;over c^2}\n\nwhere G is the gravitational constant, m is the mass of the object, and c is the speed of light. For an object with the mass of the Earth, the Schwarzschild radius is a mere 9 millimeters — about the size of a marble.\n\nThe mean density inside the Schwarzschild radius decreases as the mass of the black hole increases, so while an earth-mass black hole would have a density of 2 × 1030 kg/m3, a supermassive black hole of 109 solar masses has a density of around 20 kg/m3, less than water! The mean density is given by\n\n    &#92;rho=&#92;frac{3&#92;,c^6}{32&#92;pi m^2G^3}\n\nSince the Earth has a mean radius of 6371 km, its volume would have to be reduced 4 × 1026 times to collapse into a black hole. For an object with the mass of the Sun, the Schwarzschild radius is approximately 3 km, much smaller than the Sun's current radius of about 700,000 km. It is also significantly smaller than the radius to which the Sun will ultimately shrink after exhausting its nuclear fuel, which is several thousand kilometers. More massive stars can collapse into black holes at the end of their lifetimes.\n\nMore general black holes are also predicted by other solutions to Einstein's equations, such as the Kerr metric for a rotating black hole, which possesses a ring singularity. Then we have the Reissner-Nordström metric for charged black holes. Last the Kerr-Newman metric is for the case of a charged and rotating black hole.\n\nThere is also the Black Hole Entropy formula:\n\nS = &#92;frac{Akc^3}{4&#92;hbar G}\n\nWhere A is the area of the event horizon of the black hole, &#92;hbar is Dirac's constant (the "reduced Planck constant"), k is the Boltzmann constant, G is the gravitational constant, c is the speed of light and S is the entropy.
1098294
no. The definition of black hole is that what comes in, never comes out anymore.\n\n"What goes in must come out?" is a saying, not a law of physics
432010
a black hole is a region of spacetime from which nothing can escape because of gravity, and yes, they exist.  this was not a very detailed answer, but i may write more later.  you can follow the link below.\n\nhttp://en.wikipedia.org/wiki/Black_hole
357992
i dont believe so, from watching many episodes on nova , i understand black holes to be tinny[ in size] particles of compressed matter , so compressed as to create an astronomical gravitational force so strong that even light cannot escape. i believe most scientist believe it is a large compressed star; a star the size of our sun compressed to the area of a marble or tennis ball which because of its great gravitational force act like a celestial vacuum cleaner... its real esoteric b.s.
1117575
It is precisely that the density of a black hole is beyond the scope of reality that makes a black hole what it is - a singularity. In mathematics, a singularity is a point at which an equation cannot be solved. A simple example is 1/x, which is undefined at 0. In a black hole, the laws of physics have no solution.\n\nThe atomic bomb has nothing to do with this. Radioactive material like plutonium will explode in a runaway chain reaction if sufficient mass is brought together. (An explosive mass of radioactive material is called a prompt critical mass.) This only works with highly radioactive materials and involves no compression, whereas anything will form a black hole if sufficiently compressed. Compressing matter to this level is far beyond our current capabilities, however; it takes the collapse of a massive star to make a black hole.
1095953
There are no black holes close enough for a terrestrial probe to reach them yet. According to current theory, the intense gravitational field would trap any electromagnetic signal the probe might be sending out after it crossed the event horizon, so we wouldn't know what happened in any event.
529002
The obvious answer is black holes. But other kinds are non reflective nebulae and dark matter.
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.
32519
A Yahoo Search for black holes turns up a bunch of useful sites:\n\nhttp://search.yahoo.com/search?p=black+holes&y=Search+the+Web&ei=UTF-8&fr=sbc-web&x=wrt\n\nThe Wikipedia article is a good start:\n\nhttp://en.wikipedia.org/wiki/Black_hole\n\nAnother really good starting place is Stephen Hawking's new book "A Briefer History of Time".  Which is an update to his previous book "A Brief History of Time"\n\nhttp://shopping.yahoo.com/search?fr=ytff1-&p=A+briefer+history+of+time&ei=UTF-8&cop=mss
241248
try here\nhttp://en.wikipedia.org/wiki/Black_hole