Update on black holes from LHC

Researchers find it would require 2.4 times less energy to create a black hole than thought

It's been quite a while since I've gone looking for this topic, but here's an article that says it may be easier to make one (based on your standard old physics) than previously thought, but it's still hard:

Researchers know that it is theoretically possible to create black holes because of Einstein's Theory of Relativity—particularly the part describing the relationship between energy and mass—increasing the speed of a particle causes its mass to increase as well. The computer model in this effort, which is based on Einstein's theories, provides a virtual window for viewing what happens when two particles collide—they focus their energies on each other and together create a combined mass that pushes gravity to its limit and as a result spawns a very tiny black hole. That result was expected—what was surprising was that the team found that their model showed that such a collision and result would require 2.4 times less energy than has been previously calculated to produce such a tiny black hole.

The team also notes that despite fears of researchers building a collider to replicate in real life what their model depicts—and in the process creating a black hole that would swallow the Earth—the science just isn't there yet. It would take billions of times more energy than even the LHC is able to generate and use. Also, even if they could create such a black hole, it would disappear just as quickly as it appeared, due to Hawking radiation.

The concern about black holes, though, used to be about the relatively low energies they could be created at if there were "extra dimensions" such as string theory predicts.  I don't think this present article is about that at all...