# Space time black holes

1. Nov 15, 2011

Can the amount of space/time warped by a black hole be measured and if so, where can I find measurements of previously measured black holes?

2. Nov 16, 2011

### Staff: Mentor

All things with mass or energy cause curvature of spacetime. The amount of curvature depends on the amount of mass/energy and the distance from it. Unfortunately I do not know the math to calculate all that.

3. Nov 16, 2011

### chroot

Staff Emeritus
Black holes are very special in that the only qualities they possess are mass, charge, and angular momentum. If you know the value of those three qualities, you can calculate everything else about them, including their surface gravity. For the simplest case, a black hole with no charge and no angular momentum (i.e. non-rotating), the http://en.wikipedia.org/wiki/Surface_gravity#The_Schwarzschild_solution" provides a simple result.

Astronomers have observed black holes with masses of 18 billion times that of the Sun; you can plug that value into the Schwarzschild solution and compute the gravitational "strength" of the largest black holes known.

- Warren

Last edited by a moderator: Apr 26, 2017
4. Nov 16, 2011

Thanks you for your answers they helped a lot i dont know much about astronomy and im trying to learn and understand as much as i can.

5. Nov 18, 2011