# Curving space at speed of light?

1. Jan 13, 2010

### Johanpoan

As something approaches the speed of light the objects relative mass is increasing.
When the relatvie mass is increasing it increases in gravity.

When it's close to the speed of light it's closer to curve space-time infinitely?

What happens when space-time is curved really much around an object?

Is it closer to eveything around? :)

Is everything at the same place since gravity is infinite at the speed of light? :P

Last edited: Jan 13, 2010
2. Jan 13, 2010

### Mentz114

With respect to what ? There is no absolute motion so you can only talk about relative velocity between two frames.

I don't think so.

You get a black hole and an horizon.

3. Jan 14, 2010

### Johanpoan

Where the object was for one second ago compared to where it is now for instance .

But big masses as the earth, stars etc. curves spacetime abit because of their masses and volumes? Does objects that gain relative mass because of their speed when they're approaching the speed of light not create gravity?

4. Jan 14, 2010

### Dmitry67

No (common misconception)
Gravity is created by the REST mass + (in dynamic cases) by the other elements of the stress-energy tensor

As an example, say, there are 2 bodies (say, Earth and Moon) attracting to each other with the force of F
If they will be moving very fast their attraction will be lower F=F0/SQLRT(1-v^2/c^2)

5. Jan 14, 2010

### Johanpoan

And there it seems as relative mass contributes to gravity.

So it's actually the inverse? The closer an object is to the speed of light the less gravity force it has on other objects?

But a comet or some satelite travelling at close to light speed out of our solar system not in orbit of anything special. What will happen if it is passing an object? Does it have close to no affection in gravity force on the object it's passing becouse of your formula above?

Last edited by a moderator: Apr 24, 2017
6. Jan 14, 2010

### Dmitry67

I guess the tread you quoted have a very good explanation:

Last edited by a moderator: Apr 24, 2017