# Mass increase

## Main Question or Discussion Point

What ive learned is that when going at a fraction of C, the energy put into the acceleration is transferred into mass. However what is strange is that its gravitational strength does not increase. People keep saying that gravity is a property of the invarient mass and that alone.

So then where does that energy go to? For all that is concerned, and increase in mass without an increase in gravity is like adding 1 to infinity. This then means that any mass increase does not increase gravitational strength, thereby concluding that:

A) Gravity is a property of n number of particles, rather than a term of mass (Since then all similar fundimental particles would have similar masses)

or

B) Gravity is not a property of matter.

Related Special and General Relativity News on Phys.org
Gravitational strength does increase.

Right, then at sufficiently high speeds particles would become black holes.

That wasnt my question...

HallsofIvy
Homework Helper
Then what was your question? You started by saying, "However what is strange is that its gravitational strength does not increase. People keep saying that gravity is a property of the invarient mass and that alone."

The two replies both said, essentially, "No, that's not true".

And your only response is, "That wasn't my question"??

Dale
Mentor
People keep saying that gravity is a property of the invarient mass and that alone.
In GR gravity is not a property of the invariant mass. Gravitation comes from the http://en.wikipedia.org/wiki/Stress-energy_tensor" [Broken]. This is a Lorentz tensor, so it is obviously much more complicated than the invariant mass which is just a Lorentz scalar.

Mass alone is the source of gravity for Newtonian physics, but in Newtonian physics it doesn't make much sense to speak of invarient mass.

I would say your B) is correct. Gravity is not a property of matter. Things like charge, spin, and mass are properties of matter.

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