Is gravity zero at the centre of a black hole?

Question

My reasoning is: If it was possible to dig a tunnel to the centre of the earth, at the actual centre the mass of the earth would be equally distributed all around you and would cancel itself out; you would effectively be weightless?

Does the same reasoning apply to the singularity of a black hole, indeed does a singularity have a centre. If I am correct in my reasoning, what implications does this have, ie having a zero gravity adjacent to infinite gravity.

Answer 1

Well they don't have infinite gravity because it is still a function of their mass. It seems reasonable to say that the same principle applies to black holes as to the earth. The center should be zero gravity.

The only objection to your claim of zero gravity at the center of the earth should be that there is a lot of gravity but it is all canceled out. You would be weightless. For people who can't hypothesize for the sake of argument, the *matter* at the very center of the earth is weightless.

Answer 2

The singularity of a black hole technically does not have a "center" as the singularity itself is a point. It is infinitely small, and therefore has infinite density. The extreme turbulence caused by the gravity and mass of the singularity creates the "event horizon", a sphere around the singularity. That is the point of not return. If something goes in past the event horizon, even light, it will be compressed into infinite density.

A black hole does not have infinite gravity, because infinite gravity would require inifnite mass, which a black hole does not have. Mass from a black hole is constantly released as Hawking Radiation. So, at one point, a marble could have more mass and therefore gravity than a black hole.

In order to get an idea of the size of the singularity, imagine a pinhead. Now make it one hundred times smaller. Now make it one hundred million times smaller. Do that a couple trillion times more. Now do that a few octillion times more. You're an infinite amount of times bigger than the singularity of a black hole. In other words, a singularity is the smallest size something can be without not existing.

Answer 3

Actually, if you were at the exact center of the Earth you would have tremendous pressure pushing on you from every point and it would eventually crush you into a tiny ball of matter.

As for a black hole, I believe the theories are that the gravity is so strong it crushes all matter to a tiny ball of almost infinite density. This is the singularity. I don't know if there are any real theories about what happens to the singularity over time, but I have never heard anything to suggest there is essentially zero gravity at it's center.

Answer 4

The mass and gravity of any celestial body is concentrated at the center from above the surface.
Your reasoning about the earth is right.
If a black hole could exist when you penetrated the event horizon the mass and gravity would still be concentrated at the center and as you approached the center no mass or gravity would be above you so you would get heavier.
The escape velocity at the surface of a black hole is greater than the speed of light so if you penetrated the surface your speed would have to increase which could not happen

Answer 5

The definition of a black hole is a mass that is infinitely dense (thus infinitely small), with an infinite amount of gravitational force.... by definition there is no real center of a black hole.

Gravity Zero is something that could only be attained if The open Universe theory is correct....Even so, no creature could ever experience it, as everything that has mass has a gravitational pull, so, the creature itself would be a source of gravity.

Answer 6

A black hole must of necessity be spherical or an oblate spheroid. By symmetry gravity at the center of the black hole must be 0, increasing rapidly to a value at the Schwartzchild Radius which prevents light from escaping. The gravity at this radius is not, however, infinite.

Answer 7

Your reasoning is valid, but practically, it cannot be applied to the singularity, as it is a quark of nature, something totally "unnatural", and beyond our ken. To my limited knowledge, the definition of singularity *is infinite mass; hence infinite gravity. You will never reach the center of the singularity. It has no center. It is a point with no dimensions.

Answer 8

There is no sphere of mass at the center of a black hole. There is a dimensional singularity at the center of black hole where the laws of physics as we currently understand them break down entirely because of the rip in space time created by the singularity of the black hole. Your assumptions are incorrect. Edit: For the response below me: the inner core of the Earth is SOLID, not liquid, as stated. because of the high pressure. The state of matter defintely does matter.

Answer 9

Yes, at the centre of that (if one can go to the centre), the gravity should be zero since all around you, the mass is distributed.

Answer 10

Certain details of a black hole may be unknowable, in the sense that certain quantum properties cannot be ascertained, such as the position of a particle whose momentum is known. The Heisenberg Uncertainty Principle may apply to black holes.