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VIOLATION OF THERMODYNAMICS. “We have seen that if the body can be lowered adiabatically all the way down to the black-hole horizon, as previously assumed in the literature, then for black holes in the near-extremal regime the resulting increase in the black-hole surface area (entropy) may become too small to compensate for the loss of the body’s entropy.” https://lnkd.in/d3sfhP6 View in LinkedIn

THE PHILOSOPHER’S DILEMMA. “Very often, when we make general statements, there is an explicit or contextual restriction. ‘All ravens are black’ is a generalization about ravens. When leaving a plane with my wife, she might ask, “Were you sure to take everything?” Clearly that refers to the possessions that I brought onto the plane (and perhaps such of hers as she took me to be responsible for). So a negative answer would not be implied by my not having taken the inflight magazine or the airsickness bag from the picket in front of my seat.” https://lnkd.in/d9K-JQv View in LinkedIn

ACKNOWLEDGEMENT. “In memory of Prof. Jacob D. Bekenstein (1947–2015), whose seminal papers have inspired my research.” https://lnkd.in/d3sfhP6 View in LinkedIn

THE SAVING GRACE. “Finally, we have explicitly shown that the increase in black-hole entropy, which is a direct consequence of the (generalized) hoop conjecture, when combined with the Bekenstein entropy bound, ensures the validity of Bekenstein’s GSL in this historical gedanken experiment.” (GSL = the generalized second law of thermodynamics). https://lnkd.in/d3sfhP6 View in LinkedIn

THE LOOPHOLE. “We have proved that a new (and larger) horizon is already formed before the body reaches the horizon of the original near-extremal black hole.” https://lnkd.in/d3sfhP6 View in LinkedIn

PARADOX SOLUTION. “In order to resolve this apparent violation of the GSL, we have suggested to use a (generalized) version of the hoop conjecture.” (GSL = the generalized second law of thermodynamics). https://lnkd.in/d3sfhP6 View in LinkedIn

THE PARADOX RECAP. “In the present paper we have highlighted a non-trivial aspect of Bekenstein’s historical gedanken experiment: We have shown that if the body can be lowered slowly all the way down to the black-hole horizon, as previously assumed in the literature, then for near-extremal black holes the resulting increase in black-hole surface-area (due to the assimilation of the body by the black hole) may become too small to compensate for the loss of the body’s entropy.” https://lnkd.in/d3sfhP6 View in LinkedIn

STRESS TEST POSITIVE. “In particular, it was shown by Bekenstein that, in the regime r+(r+ − r−) ≫ μR of black holes which are far from extremality, an entropy bound of the form ensures the validity of the GSL in the famous gedanken experiment in which an entropy-bearing spherical body of radius R and proper mass μ is slowly lowered into a black hole.” (GSL = the generalized second law of thermodynamics). https://lnkd.in/d3sfhP6 View in LinkedIn

DERIVATIVE 2ND LAW. “Following this bold conjecture, Bekenstein proposed a generalized version of the second law of thermodynamics, according to which the sum of black-hole entropy...and the ordinary entropy of matter and radiation fields in the black-hole exterior region never decreases.” https://lnkd.in/d3sfhP6 View in LinkedIn

Floral structures are insatiable for form diversity. View in LinkedIn