CERN can't make black holes with their particle collider. There isn't enough energy present for that; we've talked about that one before.
So what about the other ones? The "strangelet" and the "fragile space-time"?
The notion is that a strangelet--a particle made with one or more strange quarks--would, if it contacted ordinary matter, cause it to become strange matter, and then on and on until the entire Earth had become strange matter, hyperdense and uninhabitable.
(Query: everything becomes strange matter. How could we know that hasn't already happened?)
In order for ordinary matter to become strange matter, it would have to give off energy in the process. Nothing happens in cascade like that unless there's a "downhill" to go to. It's not going to be a process that requires energy input, that's for sure. How much energy does it give off? Is it enough to cause the process to stop because the strangelets are now too energetic to remain in contact with normal matter?
I don't see it. The idea that ordinary matter is somehow more energetic than strange matter and can collapse into strange matter just sounds wrong to me. And you'd think it would have done so by now if it could, considering that the age of the observable universe is something like fifteen billion years.
"Fragile space-time"--if supernovae and quasars and all the other high-energy cataclysmic events we see across the universe aren't enough to cause a "four-fold crossrip" and end the universe, our frickin' particle accelerators sure as hell aren't gonna do it. Be your age.
* * *
As for me, tired.