We know that they have extremely powerful gravity fields, but do they actually move in space? Once it appears, is it a point of gravity/extremely dense sphere of matter that stays at that exact location or can/does it orbit around other objects?
EX: a black hole that is orbiting around another stronger black hole

They orbit around the centers of galaxies i think, most galaxies have supermassive black holes in the center of them anyway.

Black holes have the same velocities of the stars they once were, stuff like supernovae and shit can also send them hurdling through space.

Any object can be gravitationally affected by another object of equal or higher mass, and sometimes objects of lower mass (I'm not sure about this; I have only a basic understanding of how stuff like this works.). So, a black hole could by affected by the gravitational pull of another black hole, or by that of a much larger object of lower density. At any rate, they are affected by gravity. They just happen to exert a lot more of a pull than most other objects.

I would think that any mass would affect the gravity of any other mass.
If there were matter that had no gravity would it have mass?

Quote from: RomanClock;1185651I would think that any mass would affect the gravity of any other mass.
If there were matter that had no gravity would it have mass?

No. Everything that exists has mass which has gravity. So basically you're describing nothing i think.

Yes, they're called rogue black holes. They are from the small end of red giant stars, I think.

Also I don't really think there's such thing as a stationary object because of gravity and all, think of it like a balance. Heavier objects in relation to lighter objects make the fulcrum move towards it. This way, things aren't really revolving around other things, the two objects are mearly revolving around a focal point in their gravities.

I so didn't steal that from the History Channel.

Let me clarify this. Yes.

Black hole gravities can interact with each other, planets, asteroids, particles, leptons, whatever. There's no magic exception saying that it wouldn't, no matter how insignificant the effect on the black hole may seem.

Quote from: LINK, THE HERO OF TIME;1186197Also I don't really think there's such thing as a stationary object because of gravity and all.

Doesn't mean there won't be. See the second law of thermo and factor in the momentum we've been coasting on since the big bang. If the distance doesn't slow things to a stop, the temperature will.

Quote from: LINK, THE HERO OF TIME;1186197Also I don't really think there's such thing as a stationary object because of gravity and all.

Doesn't mean there won't be. See the second law of thermo and factor in the momentum we've been coasting on since the big bang. If the distance doesn't slow things to a stop, the temperature will.

Yes, first paragraph:

http://space.newscientist.com/article/dn13166-biggest-black-hole-in-the-cosmos-discovered.html

Quote from: RomanClock;1185651I would think that any mass would affect the gravity of any other mass.

True.
 

Quote from: RomanClock;1185651If there were matter that had no gravity would it have mass?

Gravity is the result of mass and not vice versa.

Quote from: Preaching Hanar;1185695No. Everything that exists has mass which has gravity. So basically you're describing nothing i think.

Um, what about light?

Quote from: GreyClock;1186303Um, what about light?

Actually, I was alluding to whether light has gravity, but its just so insignificant that it doesn't matter.
Example: If you were in a prefect vacuum shining a light on a mass, would the force of the light push it in the same direction as the light or would gravity of the light (if it has any) affect its direction?

Quote from: RomanClock;1186952Actually, I was alluding to whether light has gravity, but its just so insignificant that it doesn't matter.
Example: If you were in a prefect vacuum shining a light on a mass, would the force of the light push it in the same direction as the light or would gravity of the light (if it has any) affect its direction?

Have you ever heard of a Nichols radiometer, or for that matter, solar sails? Light can move things. As for the gravity of light, it is quite a small value compared to it's momentum.

And yes, light has momentum. It consequently has mass, it just doesn't have rest mass. Once it's done work, it's done.

F = GMm/R²

where M is mass 1 and m is mass 2, G is the universal gravational constant, and R is the distance between the two object's center points. As you can see as long as there is mass there are no exceptions. You apply a force on a star 16 million km away and it applies a force on you. It's just that since R is squared the force will be absolutely minuscule.

The great thing with the equation above is that from it you can find the acceleration of any object at the surface of the earth.
G = 6.67300E-11 m^3 kg^-1 s^-2
M =  5.9742E24 kg
R  = 6 378.1 km

F = ma
F = GMm/R²

m's cancel out

a = GM/R²
a = ~9.8m/s²

And if you ask me, "What about light, it has no mass?", well then look no further than the comment above me by SolenoidClock.

black holes are a singular piece of matter, so dense that they have a massive amount of gravity, black holes are definitely affected by gravity, they are created by gravity!

Why are people still posting in this thread? I think we've established that yes, black holes are affected by gravity. Also, there's not need to bring equations into this. Nobody's trying to figure out how much they're affected (in this thread, anyway). Therefore, you don't need to get into complex, mind-numbing detail. Or maybe I'm just I'm a edgy teen when it comes to math. That answer seems most likely.

Quote from: ONIONATOR;1187081Why are people still posting in this thread? I think we've established that yes, black holes are affected by gravity. Also, there's not need to bring equations into this. Nobody's trying to figure out how much they're affected (in this thread, anyway). Therefore, you don't need to get into complex, mind-numbing detail. Or maybe I'm just I'm a edgy teen when it comes to math. That answer seems most likely.

This thread is not just about the initial query, but to address a string of question derived from other answers relating to black holes.

Quote from: RomanClock;1187083This thread is not just about the initial query, but to address a string of question derived from other answers relating to black holes.

Alright. I'll be on my merry way then.

Quote from: Monterey Jack;1186212Doesn't mean there won't be. See the second law of thermo and factor in the momentum we've been coasting on since the big bang. If the distance doesn't slow things to a stop, the temperature will.

Not a true stop, though. A constant decrease of energy, yes, but functioning as a division, not a subtraction, so nothing with any mass has 0 energy. Plus, the leaving energy is not destroyed, but just transferred to the nearest objects, and those objects and the energy it's self will have gravitational force, creating more movement.

When is there a case of energy turning into matter? We can turn matter into energy, but how do we do the other way around? Doesn't that mean eventually all matter will be converted into energy?

Quote from: RomanClock;1187576When is there a case of energy turning into matter? We can turn matter into energy, but how do we do the other way around? Doesn't that mean eventually all matter will be converted into energy?

no, not necessarily

Quote from: ZeitmiserZeitmesser;1187562Not a true stop, though. A constant decrease of energy, yes, but functioning as a division, not a subtraction, so nothing with any mass has 0 energy. Plus, the leaving energy is not destroyed, but just transferred to the nearest objects, and those objects and the energy it's self will have gravitational force, creating more movement.

Right. I was only meaning to refer to macroscale objects though. Zero point energy and isentrophy will always keep things interesting.