# Questions for a physicist

1. Sep 9, 2010

### Philos

I have a few questions and I hope they can be answered here.

1. Does a perfect black body gain mass?

2. Does matter implode local space-time or does space-time curve around matter or are both of these assumptions wrong? If wrong what process happens?

3. Does increasing the energy state of a particle also increase its mass?

2. Sep 13, 2010

### bcrowell

Staff Emeritus
Hi, Philos --

Welcome to Physics Forums!

It depends on the radiation in its environment.

There's no way to answer this unless it's phrased in more exact language.

This depends on your precise definition of mass.

Your questions aren't sufficiently well defined to be answerable. If you tell us your background in math and physics, we might be able to help you get unstuck from the stage where you're currently stuck: not succeeding in formulating good questions.

3. Sep 14, 2010

### michael879

If the energy density in its surrounding environment is less than the power it radiates, yes. Otherwise no, it will radiate energy and lose mass.

I'm not really sure what your asking but it sounds like an interpretation issue. If your asking what I think your asking, nobody knows. Its like asking how a charge generates E&M fields, or if the E&M fields are what generate charges. The equations governing the theory don't specify and there is no way to really know (unless the theory is wrong).

If its localized energy yes. For example, exciting an electron in an atom will increase the mass of the atom. However, kicking a free electron to speed it up will not increase its rest mass (it will increase its relativistic mass but I don't like using that term)

4. Sep 21, 2010

### laQuinta

I'm responding to #2. If spacetime curvature is imagined as lines of force, they do NOT curve around matter, but rather link directly to/from the center of each and every mass body in the universe (from quanta to planets and suns). The "curving" aspect comes from the interaction of all those local lines from each mass. The earth has its spacetime "curvature" and I have mine. In freefall, I would feel wightless as I rushed toward Earth (and she nudged toward me). When I got to the surface, I would suddenly "feel" the force of that earth's spacetime curvature because earth's surface would stop my natural motion before I reached her CENTER of gravity.

Or that's my take on it.