By investigating quantum gravity at the horizons of black holes, a new model suggests that black hole evaporation might appear identical to elementary particle decay. Image credit: Coyne and Cheng.
(PhysOrg.com) -- In trying to understand how gravity behaves on
the quantum scale, physicists have developed a model that has an
interesting implication: mini black holes could be everywhere, and all
particles might be made of various forms of black holes.
The scientists, Donald Coyne from UC Santa Cruz (now deceased) and
D. C. Cheng from the Almaden Research Center near San Jose, are
cautious about the idea, but say that it's worth investigating with the
Large Hadron Collider
(LHC) and other high energy physics experiments. Cruz and Cheng have
presented their idea in a study posted on arxiv.org, "A Scenario for
Strong Gravity in Particle Physics: An alternative mechanism for black
holes to appear at accelerator experiments."
As the physicists explain, gravity is considered an
astronomical-scale force; its effects on smaller scales seem to be
virtually nonexistent. However, as the scientists write, "it has often
been assumed that near the Planck scale, gravity would somehow assert
itself and become comparable in strength to the other forces of nature,
likely as a product of some grand unification picture." Coyne and Cheng
approach the problem of small-scale gravity by presenting a new model
of black hole evaporation. As black holes lose energy, they slowly
evaporate, shrinking in size down to the quantum scale - where they may
be identical to elementary particles.
The new model assumes "that gravity is truly strong and fully
comparable with other forces, but that we have not experimentally
looked in those places where it resides," the authors write. "But
instead of invoking extra dimensions and branes, we look elsewhere. An
obvious place where experimentalists have not tested gravity, in any
way, is directly at the horizons of black holes of sufficient
temperature such that quantum gravity could be operative. We speculate
that at this level, the spacetime structures of the horizons could be
far more complex than those predicted by general relativity. They might
well require more degrees of freedom to stipulate a particular state,
and they might leak information; i.e., not be true horizons in the
usual sense of the word. Most important, if gravity on or within these
horizons is truly strong, yet we see no evidence of that on larger
scales, then the complex horizons must be shielding in nature." A
shielding pseudo-horizon, they say, is an unconventional speculation,
as it suggests that gravity is a very strong force but is substantially
shielded.
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Full article: http://www.physorg.com/news161857121.html
