Somewhat related scenario: There were concerns about the Large Hadron Collider before it was turned on. (And, I vaguely remember reading, to a lesser extent about a prior supercollider.) Things like “Is this going to create a mini black hole, a strangelet, or some other thing that might swallow the earth?”. The strongest counterargument is generally “Cosmic rays with higher energies than this have been hitting the earth for billions of years, so if that was a thing that could happen, it would have already happened.”
One potential counter-counterargument, for some experiments, might have been “But cosmic rays arrive at high speed, so their products would leave Earth at high speed and dissipate in space, whereas the result of colliding particles with equal and opposite momenta would be stationary relative to the earth and would stick around.” I can imagine a few ways that might be wrong; don’t know enough to say which are relevant.
Somewhat related scenario: There were concerns about the Large Hadron Collider before it was turned on. (And, I vaguely remember reading, to a lesser extent about a prior supercollider.) Things like “Is this going to create a mini black hole, a strangelet, or some other thing that might swallow the earth?”. The strongest counterargument is generally “Cosmic rays with higher energies than this have been hitting the earth for billions of years, so if that was a thing that could happen, it would have already happened.”
One potential counter-counterargument, for some experiments, might have been “But cosmic rays arrive at high speed, so their products would leave Earth at high speed and dissipate in space, whereas the result of colliding particles with equal and opposite momenta would be stationary relative to the earth and would stick around.” I can imagine a few ways that might be wrong; don’t know enough to say which are relevant.
LHC has a webpage on it: https://home.cern/science/accelerators/large-hadron-collider/safety-lhc