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what about a black holes surface temperature (read details)?
for having an idea....
a black hole has a surface which must not necessarily be the same as the diameter of its event horizon.
This is (as far as i know) depending on the BH size and should make it possible for certain types of BH to have some Space between EH and surface.
So ok we can't observe the surface...
what will happen if this surface get heated up, lets say by infalling matter in hughe ammounts (neutron star or bigger).
Is it heating up ? will it do so ?
or not ?
and if so CAN it heat up endlessly ?
15 Answers
- Mercury 2010Lv 71 decade agoFavorite Answer
wow. you really like black holes don;t you?
the heat would be devoured like the rest of energy and matter.
all that light and matter inside a black hole beign compacted has to create some kind of massive levels of heat, it just can't escape into our universe
I'm sure it adds upon itself, but reality is so multilated and compacted, I don't know if heat could even still have a normal effect.
I think there are universes inside a black whole. and in those universes, matter and energy from the black hole are released to create big bangs.
- 1 decade ago
Well... from what *I* know about black holes - they're all essentially dimensionless points. They occupy zero space. God divided by zero, and got the black hole.
Now, the only indication to how massive a black hole really is can be seen by how big the diameter of the event horizon is. The event horizon is the border of 'normal' space, and the realm of the black hole.
Figure: if Earth were to collapse to a dimensionless point, a black hole would form, with an event horizon of about 1/2 the size of a golf ball. For Jupiter, again - the actual mass would be a single quantum point in space, but the event horizon would be about 30 feet in diameter.
The event horizon is the point out in space where the orbital velocity of the black hole is the speed of light. Doesn't matter how 'big' the black hole is (because none of 'em have a true size) but the location of the EH is directly dependend on how much mass the black hole contains.
As for heating... When a black hole forms, it's the core of a star, and it's super-hot - say, 60 million degrees. For one thing, electromagnetic energy can't escape the black hole. (At least, it can't escape the EH), and for another, the surface area of a black hole is nearly (or is) non-existent - meaning, heat **can't** escape.
After our sun finishes it's red giant phase while dying, and blows off it's outer layers, a super-hot white dwarf about the size of the Earth will remain; it'll gradually cool - but it's cooling will be MUCH slower because of it's small size. Now, imagine a black hole that has *no* size - it will be likely hot forever.
- Anonymous1 decade ago
I am not sure to understand the BH theory but I believe that they are a point or a flat disk. I don't understand how a surface exist there. The temperature is the moving of particles, but as the BH have no volume, nothing can move there. Probably the matter irradiates most of the heat before reach the EH and the remaining heat becomes kinetic energy (the BH spin) .
The matter falling to a BH (but outside the EH can be heated to a high temperature so the radiation removes fast most of the heat.
- 1 decade ago
This is a great question! I can't come up with any way to explain how a space could exist between the event horizon and the surface. To me the temperature of a black hole while in a state of not absorbing more matter must be close to absolute zero because there is no activity whithin it. However if it is impacted by a large mass of neutrons there has to be thermal activity, if none this radiation can escape it must be because it absorbed quickly by the tremendous mass of the black hole. There is no way that it can heat up endlessly. If a giant star in the neighbourhood of a black hole could, somehow, collapse into a mass of anti matter and be pulled into a black hole, that would be a very interesting thing to observe, it could be the mother all exlosions.
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- cosmoLv 71 decade ago
The classical "black hole" solution to the equations of general relativity is a vacuum everywhere, except for the infinitely dense singularity at the center. If you fell in from a distance, you would never see any surface, or indeed anything nearby at all as you fell in, although if you looked back on the outside universe it would get faster and faster and brighter and brighter. There would be a flash due to external radiation as you passed the event horizon.
A star that collapses to form a black hole is a different matter. There is an inwardly-moving surface, and if the star still has some internal pressure you might be able to catch up to it. The surface will fall into the singularity, and you'll fall in after. The star will heat up as it is compressed, to the extent that it still has some internal pressure.
- jimschemLv 41 decade ago
What exactly is heat?
In hotter gas or air the molecules move faster and posses
more kinetic energy.
In hotter liquids, it's the same, the molecules move faster.
In solids it is slightly different, the atoms of a metal or molecules of a solid are not free to move about but must vibrate in place. The vibration and kinetic energy increases with temperature.
In neutron stars as well as BHs atoms are crushed out of existence, atoms are nonexistent. In neutron stars electrons have been paired up with protons and merged into neutrons.
The shoulder to shoulder neutrons vibrate. The vibration is
translated to heat, very hot indeed.
However, in BHs, the 3 quarks in each neutron have been squeezed together, so there are no normal particles either.
In BHs, we don't know what particles are left if any. The singularity at the center of BHs is said to be a geometrical point, of zero volume, infinite density.
I ask you, what could be moving or vibrating in zero volume?
I believe the concept of heat in a singularity may be outside the realm of possibility.
You use the word surface 5 times in your question.
What is the surface area of a sphere of zero radius?
- 1 decade ago
First of all I want to start out by saying that a black hole does not have a surface. It's a singularity that has warped space-time in on itself. Now a black hole's temperature is determined by the black body radiation temperature of the radiation that comes from it. For black holes the mass of our Sun, the radiation coming from it is so weak and so cool that the temperature is only one ten-millionth of a degree above absolute zero. This is colder than scientists could make things on Earth up until just a few years ago (and the invention of a way to get things that cold won the Nobel prize in 1997). Some black holes are thought to weigh a billion times as much as the Sun, and they would be a billion times colder, far colder than what scientists have achieved on Earth.
However, even though these things are very cold, they can be surrounded by extremely hot material. As they pull gas and stars down into their gravity wells, like you said, the material rubs against itself at a good fraction of the speed of light. This heats it up to hundreds of millions of degrees. The radiation from this hot, infalling material is what high-energy astronomers study.
So no, the black hole is not heating up, however it can "cause" a lot of heat.
- Tim CLv 51 decade ago
ok first of all you have some terms confused, a black hole is defined as the area within the vent horizon. the singularity could be up to the diameter of the black hole. almost all black holes would have space between the singularity and the event horizon as far as we know.
will it heat up? no
all energy will be pulled into the center, all matter as it falls into a black hole gets stretched, spaghettified to use the scientific term. stretched one way, crushed the other way, this heats up the matter incredibly, to the point that the matte will emit x-rays and other radiation.
but once it passes the event horizon, its gone, no heat, nothing.
keep in mind that as a black hole "feeds" it grows as well, and the surface temperature of a black hole depends on its size. the larger the hole the cooler it is. so as mass falls in, this hot matter added energy to the black hole, in any other circumstance it would heat it up, but black holes are special, nothing gets out. the heat and matter would just feed it, making it grow bigger and colder.
- Anonymous1 decade ago
The singularity is infinitely small and nothing can escape from beyond the event horizon, including infrared (heat) energy.
We cannot know what is going on inside the black hole because the effects beyond the event horizon are not observable.
Black holes can eventually lose heat and mass by the creation of virtual pairs of particles near the event horizon. When one particle falls into the black hole, the other particle becomes real, taking away heat and mass.
- 1 decade ago
Well, I'm no physicist, but logically it seems to me that if energy, in the form of mass, is crossing the event horizon then the heat of that mass must go somewhere.And since nothing can escape a BH then yes, it must heat up.
Whether there is an upper limit to that heating, I have no idea :)