<p>I am puzzled by this question, because by the laws between the two object the relative gravitation force should be infinite. Anyways we can take two objects where the sum of speeds are equaling c (speed of light).</p>

<p>So the answer should be not, but many theoretical physicists making examples to demonstrate what happens if we closing to the speed of light. But what happens if we reach 90% of the speed of light and an object flies on the opposite direction by 10% of speed of light? By rational thinking there should be an extreme gravitational force between the two items.</p>

<p>All of these are true if I understood correctly the the General Relativity Theory.</p>

<p><strong>Can somebody point out what is the problem with my thinking if there is?</strong> </p>

CC BY-SA 3.0
2014-06-03T17:10:21.833Z
But for the gravitational force to be substantial, the bodies will have to be very massive and the massive they are, the more difficult it is to accelerate it to light speed. And we also have the  addition of velocities.
Yashbhatt
CC BY-SA 3.0
2014-06-03T17:14:33.863Z
This question doesn't have any particularly astronomical content. Anyway, the answer to your question is **no**: relativistic velocity addition works differently, and you simply _cannot_ add two less-than-c velocities to get a greater-than-c velocity. Also, gravity needn't enter into the issue. See [this question](http://physics.stackexchange.com/q/79331/23966) at [physics.se].
senshin
<light><general-relativity><speed>
Is it possible to have two objects moving by sum speed of light (c) in the opposite direction?
CsBalazsHungary
# Is it possible to have two objects moving by sum speed of light (c) in the opposite direction?

(Asked by: username_0 on 2014-06-03)

I am puzzled by this question, because by the laws between the two object the relative gravitation force should be infinite. Anyways we can take two objects where the sum of speeds are equaling c (speed of light).

So the answer should be not, but many theoretical physicists making examples to demonstrate what happens if we closing to the speed of light. But what happens if we reach 90% of the speed of light and an object flies on the opposite direction by 10% of speed of light? By rational thinking there should be an extreme gravitational force between the two items.

All of these are true if I understood correctly the the General Relativity Theory.

**Can somebody point out what is the problem with my thinking if there is?**

**Tags:** light, general-relativity, speed
> **Comments:**
> **username_1**: But for the gravitational force to be substantial, the bodies will have to be very massive and the massive they are, the more difficult it is to accelerate it to light speed. And we also have the  addition of velocities.  
> **username_2**: This question doesn't have any particularly astronomical content. Anyway, the answer to your question is **no**: relativistic velocity addition works differently, and you simply _cannot_ add two less-than-c velocities to get a greater-than-c velocity. Also, gravity needn't enter into the issue. See [this question](http://physics.stackexchange.com/q/79331/23966) at [physics.se].  

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