Does relativistic mass create a gravitational attraction?
If yes, then could an object move fast enough to have a mass high enough to become a black hole?
If yes, when the object decelerates would we be able to conclusively measure the speed of the propagation of gravity?
If no, why not?
>>7764374
>Does relativistic mass create a gravitational attraction?
No. This is part of why the "relativistic mass" concept is no longer taught, as it was confusing and led to questions like this.
>>7764383
>This is part of why the "relativistic mass" concept is no longer taught
Explain.
>>7764405
>>7764374
>If yes, then could an object move fast enough to have a mass high enough to become a black hole?
It's easy to see that the answer must be no if you consider that all velocity is relative. If you have an object moving very fast in your frame of reference, there is another frame of reference in which its velocity is zero. Neither one is any more valid than the other. Conversely, there are frames of reference in which EVERY object is moving arbitrarily close to the speed of light.
>>7764374
All mass is rest mass. Relativity does not preclude choosing the CMBR as the default rest frame. Earth spirals at some 630 km/s of cosmic velocity towards (but not relative to) the constellation Virgo.
What about angular momentum? If you make a top spin does it have more gravity?
>>7764374>>7764374
relativity nerd here
This question is stupid because it assumes the theories about black holes and how they work are true
But yes i can feasibly see what you're saying, although if black holes WERE moving at near the speed of light in a vacuum i think we would be able to observe itit (or, conversely, not be able to observe the hole at all)
>>7764383
Its not being taught because universities are idiot factories and none of us who are intelligent enough to continue what Einstein started have surfaced yet
>>7764374
This question makes me think of the micro-black holes of the LHC/etc
Quantum elements aren't compressible are they?
>>7764715
Yes.
Spinning is acceleration (constantly changing velocity) and acceleration = gravity.
Studying a spinning object in special relativity lead to general relativity and gravity.
A faster moving object has more momentum which means that the stress-energy tensor [math]T_{\mu \nu} [/math] changes which leads to a higher gravitation.
So yes, gravitation depends on momentum and thus relativistic mass.
>>7764405
"Relativistic mass" is bookkeeping to describe how objects get harder to accelerate as they approach lightspeed. In ordinary Newtonian mechanics, the mass describes how difficult it is to accelerate something, so if you're familiar with classical mechanics it's pretty easy to just pretend that faster-moving objects have increased mass and analyze their motion that way.
While convenient and allowing you to keep using a lot of methods from classical physics, it obscures the actual structure of special relativity and is a bit misleading because it applies *only* to inertia and not to other attributes of mass such as gravity.
Another question: Would an electric charge orbiting a massive object - due to gravity - emitt radiation?
