Have we ever observed microscopic black holes in the LHC?
You'd hear about it if we had.
At the energy levels used at the LHC, any microblack hole created would effectively instantly be turned into energy via Hawking radiation.
Therefore making it impossible, or improbable to observe a microscopic black hole?
Essentially, although I suppose a particle physicist could talk about the differences in what we detect in particle collisions verses what we would detect in a black hole vaporization scenario.
I remember hearing a statistic that high energy cosmic rays should produce hundreds of micro black holes a year, but none have ever been directly detected. I don't think it is really an area of current research due to the fact that it is such a rare phenomenae which is extremely hard to detect.
When a massive star orbits a supermassive black hole eccentrically, it can be accelerate to relartivistic speeds when it approaches the black hole. We have seen these dramatic u turns by stars in elegant work done over many years. Question, could these accelerating stars cross the threshhold for becoming black holes due to increased kinetic energy and hence mass?
Bodies do not form black holes due to relativistic mass increase. In its own reference frame, it has only rest mass energy and will not form a black hole unless that mass is concentrated in a volume smaller than its Schwarzschild limit. If it is not a black hole in one reference frame, it is not a black hole in any reference frame.
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