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As we know that light photon cannot escape the gravity of a black hole so I was thinking that if that is the surface of the black hole would be bright as all the photons would be there only. Am I right or wrong?

Deiknymi
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7 Answers7

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Well, a black hole doesn't have a solid surface, it has an event horizon that, as you might already know, represents a mathematical boundary beyond which no matter/energy can escape, which includes photons. Any light that the "star" may have released is no longer visible because it cannot escape, but incoming light may either fall into the hole, or "orbit" the hole just outside of the Schwarzschild radius. This light would be visible only to an indestructible observer, otherwise he would be destroyed by the sum of all forces at this stage. But the center is not "bright" because light would have to emitted and reach our eyes for us to see it.

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A photon emitted outside the event horizon can escape outwards, while a photon emitted inside the event horizon can only move inwards. The only way for a photon to be trapped at the event horizon would be for it to be emitted (by some infalling body) exactly at the event horizon.

Although this is possible, there are two problems. The first problem is that the event horizon is a 2D surface so the probability of a photon being emitted exactly at the event horizon is zero. Since photons emitted a tiny bit inside or a tiny bit outside move away from the event horizon the photon density is going to fall to zero at the surface itself. The second problem is that a photon emitted exactly at the surface would be infinitely red shifted for any external observers so it would appear dark not bright.

So the surface of the black hole, i.e. the event horizon, isn't bright.

John Rennie
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A photon can escape the black-hole if it doesn't fall into the event horizon. If the photon hits the surface, it just orbits around the black-hole through the horizon. The curvature is so strong that it can't escape through the exit light cone. Here is an image from "A Brief History of Time". This makes sense that only photons that trace above the boundary can be perceived.

My question is: "How can we perceive something when the element of perception (light or any other EM radiation - photons) can't reach us?" (It can't even escape...)

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http://www.aoc.nrao.edu/~gcnews/gcnews/Vol.11/

The link above is one example of a serious scientific simulation. It shows more light comes from the sides than the center, which looks more or less darker than the outside. This is called "seeing the black hole's shadow", and some serious astronomers expect to do it in less than ten years.

Jim Graber
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Firstly there are a lot of post with “we know” and “Yes” and “No” The simple fact is we don’t know, every bit of knowledge we have concerning black holes is theoretical, so keep an open mind, keep asking questions and don’t accept anyone answers as final.

John
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Yes the singularity of a black hole would be incredibly bright once you get to the center because the light and energy can't escape the black so it is all compressed into and infinity dense small point and even if it is just normal matter going inside the black hole it would even make it more bright because the black hole tidal forces would rip the atoms apart because it's gravity gets so strong not just that at the center of a black hole it is so dense that the atoms would heat up a lot and turn back into energy and since it is infinitely dense with a lot of energy and photons inside there all compact in a single point it will stay burning hot and bright its just we can't see the center because the gravity sucks in the light before it reaches our eyes.

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There are alot of theories about black holes.

It can take you to another universe on our multiverse, so you can say yes if you exit near a star or something.

It can give more energy to the photons that enter so you will not see it.

It can even turn the light in something else. Small chances.

But these are just some theories. By normal physics yes, you should see light, but... we know that nothing acts normaly inside a black hole so the answer is undefined. We may found it just experimentaly, and this would be a suicide mission. I think that only a type III civilization could enter a black hole and we are a milion years away from that stage of the civilization so... you can only hope that immortality and other things can occur in your lifespan. But again by normal physics the answer is YES! PS: Sorry for my bad english, I am a 12 year old boy from Romania.