black hole is made out of star, but star has volume so why black hole don't have volume
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Who told you that Black hole haven't any volume ?
Black hole keep crushing things and keep eating them and it's mass and volume were in millions time than sun. A mass of black holes can up to 20 TIMES greater than the mass of our sun.
There is no meaningful formal definition for the volume of a black hole.
The region enclosed by the event horizon contains a singularity, therefore any integral over that region would be ill-defined. Furthermore, the role of the radial and time coordinates are swapped, so it is not even possible to define a concept of volume that is consistent with what we consider as volume here on the outside. As to the singularity itself, while it is indeed characterized as infinite density, inside the event horizon it becomes a future moment in time, not a location in space. So infinite density in this case does not imply zero volume.
And of course there is the question of the role quantum physics, specifically a yet-to-be-discovered quantum theory of gravity, would play… perhaps no singularity forms in the first place. But we don’t really know.
More conventionally, the “volume” of a black hole, on those rare occasions when it is discussed at all (it is usually not a relevant concept), is often taken to be the volume enclosed by the event horizon as seen from the outside, i.e., plain old V=4πr3S/3V=4πrS3/3, where rSrS is the black hole’s Schwarzschild radius. (Of course this formula would need to be revised for rotating or charged black holes where the event horizon is not perfectly spherical.)
Nothing can have zero volume according to Quantum Mechanics. In QM no object can be confined to a region smaller than its wavelength. Point masses are convenient in Newtonian gravity calculations, but have no reality.
There is a theorem that the inverse-square gravity of a uniform sphere is equivalent to the gravity from a point mass at the center of the sphere. So we can model the Solar system with fair accuracy using point masses for the Sun and planets, or the gravity of a galaxy using hundreds of billions of point masses plus a distribution of gas, dust, and dark matter. We cannot model the Sun-Earth-Moon system in that way, because the Earth is not a uniform sphere, and tidal effects are important in that system, driving the Earth and Moon steadily apart.
QM suggests that whatever form of matter turns into a black hole or gets added to a black hole would be sorted into layers corresponding to the wavelengths of various particles, with a background of photons of a continuous distribution of wavelengths.
These particles would have to be nearly all bosons, in order to be in the same quantum state together, as a Bose-Einstein condensate. Fermions all have to be in different quantum states. They can support quite large pressures, but there are limits. In white dwarf stars electron degeneracy pressure holds up to the Chandrasekhar limit of 1.44 solar masses. At that point, or even a little below it, electrons and protons combine to form neutrons.
In neutron stars neutron degeneracy pressure holds up to the Tolman-Oppenheimer-Volkhov limit, which is not known to the same precision, but is only a few solar masses. At that point the neutrons must turn into bosons, but we have no knowledge of which ones those might be.
No other fermions that we know of could hold up under any greater pressure. Bosons can be in the same quantum state in a Bose-Einstein condensate in any quantity, up to billions of solar masses, as far as we know.
We do not know what particular bosons might form in a collapsing neutron star, and there is much more that we do not know about conditions inside a black hole, but these are fundamental principles that no proposed theory of quantum gravity provides any exceptions for. Another thing that we do know is that matter can quantum tunnel from the core of a black hole out to any distance. Nearly all of it will materialize within the event horizon and fall straight back, but some can materialize outside the event horizon and escape as Hawking radiation.
hope that helps you ⭐⭐⭐⭐!
Black hole keep crushing things and keep eating them and it's mass and volume were in millions time than sun. A mass of black holes can up to 20 TIMES greater than the mass of our sun.
There is no meaningful formal definition for the volume of a black hole.
The region enclosed by the event horizon contains a singularity, therefore any integral over that region would be ill-defined. Furthermore, the role of the radial and time coordinates are swapped, so it is not even possible to define a concept of volume that is consistent with what we consider as volume here on the outside. As to the singularity itself, while it is indeed characterized as infinite density, inside the event horizon it becomes a future moment in time, not a location in space. So infinite density in this case does not imply zero volume.
And of course there is the question of the role quantum physics, specifically a yet-to-be-discovered quantum theory of gravity, would play… perhaps no singularity forms in the first place. But we don’t really know.
More conventionally, the “volume” of a black hole, on those rare occasions when it is discussed at all (it is usually not a relevant concept), is often taken to be the volume enclosed by the event horizon as seen from the outside, i.e., plain old V=4πr3S/3V=4πrS3/3, where rSrS is the black hole’s Schwarzschild radius. (Of course this formula would need to be revised for rotating or charged black holes where the event horizon is not perfectly spherical.)
Nothing can have zero volume according to Quantum Mechanics. In QM no object can be confined to a region smaller than its wavelength. Point masses are convenient in Newtonian gravity calculations, but have no reality.
There is a theorem that the inverse-square gravity of a uniform sphere is equivalent to the gravity from a point mass at the center of the sphere. So we can model the Solar system with fair accuracy using point masses for the Sun and planets, or the gravity of a galaxy using hundreds of billions of point masses plus a distribution of gas, dust, and dark matter. We cannot model the Sun-Earth-Moon system in that way, because the Earth is not a uniform sphere, and tidal effects are important in that system, driving the Earth and Moon steadily apart.
QM suggests that whatever form of matter turns into a black hole or gets added to a black hole would be sorted into layers corresponding to the wavelengths of various particles, with a background of photons of a continuous distribution of wavelengths.
These particles would have to be nearly all bosons, in order to be in the same quantum state together, as a Bose-Einstein condensate. Fermions all have to be in different quantum states. They can support quite large pressures, but there are limits. In white dwarf stars electron degeneracy pressure holds up to the Chandrasekhar limit of 1.44 solar masses. At that point, or even a little below it, electrons and protons combine to form neutrons.
In neutron stars neutron degeneracy pressure holds up to the Tolman-Oppenheimer-Volkhov limit, which is not known to the same precision, but is only a few solar masses. At that point the neutrons must turn into bosons, but we have no knowledge of which ones those might be.
No other fermions that we know of could hold up under any greater pressure. Bosons can be in the same quantum state in a Bose-Einstein condensate in any quantity, up to billions of solar masses, as far as we know.
We do not know what particular bosons might form in a collapsing neutron star, and there is much more that we do not know about conditions inside a black hole, but these are fundamental principles that no proposed theory of quantum gravity provides any exceptions for. Another thing that we do know is that matter can quantum tunnel from the core of a black hole out to any distance. Nearly all of it will materialize within the event horizon and fall straight back, but some can materialize outside the event horizon and escape as Hawking radiation.
hope that helps you ⭐⭐⭐⭐!
Albert01:
awesome
great
A black hole has an infinite density; since its volume is zero, it is compressed to the very
The density is infinite, but the mass is still finite. So everybody seems to fall into a logical trap here.
thanks
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Black holes are a prediction of general relativity. If you input the mass of a huge star (say one hundred times that of the Sun) into Einstein's theory, you see that when the star runs out of energy from nuclear fusion, it will start to fall in on itself, and the gravitational field surrounding this collapsing star will become so huge that it will be impossible for anything - even light - to escape from it.
In Einstein's equations suggest that everything falls into a point. This point has no volume and is therefore infinitely dense. Because it has infinite properties, we call it a singularity, and are unable to make any further predictions about the matter that has gone into it. Maybe we just don't have powerful enough imaginations to understand such singularities, but physicists commonly think that they are such an absurd idea that it demonstrates the theory we are working with isn't quite perfect.
In Einstein's equations suggest that everything falls into a point. This point has no volume and is therefore infinitely dense. Because it has infinite properties, we call it a singularity, and are unable to make any further predictions about the matter that has gone into it. Maybe we just don't have powerful enough imaginations to understand such singularities, but physicists commonly think that they are such an absurd idea that it demonstrates the theory we are working with isn't quite perfect.
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