Evaporation of warped brane-world micro black holes outpaces accretion above a small critical mass

Primary source: Casadio, Fabi, and Harms, "Possibility of Catastrophic Black Hole Growth in the Warped Brane-World Scenario at the LHC," Physical Review D 80, 084036 (2009), arXiv:0901.2948 (arxiv.org/abs/0901.2948). The paper derives black hole mass accretion and decay as functions of time within the tidal-charged brane-world framework; the maximum black hole mass is a function of a critical mass parameter appearing in their luminosity expression and related to the size of extra-dimensional corrections to Newton's law. Above that critical mass, evaporation outpaces accretion, which is this claim verbatim in substance. Follow-up work by the same group (Casadio, Fabi, Harms, and Micu, "Theoretical survey of tidal-charged black holes at the LHC," JHEP 02 (2010) 079, arXiv:0911.1884; also arXiv:1002.1219 on the bulk structure of tidal-charged holes) refined rather than retracted the result.

How the subclaims weigh. The supporting fact that torsion-balance experiments bound extra-dimensional corrections to Newton's law to sub-millimeter scales↗︎ is settled experimental bedrock (Kapner et al. and successors) and secures the "small" in the claim; it carries no risk. The assumption that the tidal-charged metric validly describes brane-world micro black holes↗︎ is a conjectural effective description: at the time of the derivation no exact warped brane-localized black hole solution existed, so both the horizon scaling and the luminosity law that produce the critical-mass structure inherit that uncertainty. The requirement that brane-localized black holes in warped compactifications evaporate rather than remaining stable↗︎ is the claim's exposed flank: if evaporation fails entirely, a zero rate outpaces nothing and the claim is false. Whether these holes evaporate was conjectural in both directions: holographic arguments (Tanaka, gr-qc/0203082; Emparan et al.) suggested large brane-localized holes cannot be static and must shed mass classically, while the later static solutions of Figueras and Wiseman (2011) cut against that conjecture for large holes; the quantum evaporation rate of microscopic brane-localized holes in warped geometry has no first-principles derivation.

Why supported rather than contested. The apparent counter-analysis, Giddings and Mangano's finding of fast accretion in warped scenarios (arXiv:0806.3381), stipulates stable, non-evaporating holes as a deliberate worst case; it therefore does not assert the negation of this claim, which compares rates when evaporation operates. Plaga's metastable-hole scenario (arXiv:0808.1415) is the nearest genuine opposition, and the graph's assessment elsewhere finds it applies radiation and accretion formulas inconsistently. So the state of the argument is: one credible model-dependent derivation for, no derivation against under the same premises, and an unresolved framework premise. That is supported with moderate credence, not a two-sided dispute about the proposition itself.

Credence 0.55 reflects the product of two uncertainties: that evaporation operates at all for these configurations (expected for microscopic holes on general Hawking-radiation grounds, but unproven in warped geometry), and that the tidal-charged rate comparison survives in a correct description. What would change the conclusion: an exact or numerical treatment of evaporating micro black holes in warped compactifications confirming or refuting the critical-mass structure would move this to verified or contradicted; a demonstration that brane-localized holes are classically and quantum-mechanically stable would falsify it outright. Confidence 0.7 rather than higher because the choice between supported and contested turns on reading the stable-hole analysis as answering a different hypothesis, a judgment a reasonable assessor could weigh differently.