University of California-Santa Barbara Professor Steve Giddings said if any microscopic black holes are produced, they would exist for "about a nano-nano-nanosecond."

The study is co-authored by Michelangelo Mangano of the European Center for Nuclear Research, or CERN, which is building the world's largest particle collider near Geneva, Switzerland.

"The future health of our planet and the safety of its people are of paramount concern to us all," Giddings said. "There were already very strong physics arguments that there is no risk from hypothetical micro black holes, and we've provided additional arguments ruling out risk even under very bizarre hypotheses."

The $8 billion LHC, under construction for 14 years, is expected to begin operations in September, colliding proton beams at levels of energy never before produced to be studied, for among other things, the possibility of extra dimensions of space.

Giddings' research is to be published in the journal Physical Review D.