Year: 2022

ENTROPY AS AREA. “The analogy with the tendency of entropy to increase led me to propose in 1972 that a black hole has entropy proportional to the area of its horizon.” https://lnkd.in/draqjTW View in LinkedIn

INVIOLABLE THERMODYNAMICS. “I conjectured that when matter falls into a black hole, the increase in black hole entropy always compensates or overcompensates for the lost entropy of the matter. More generally, the sum of black hole entropies and the ordinary entropy outside the black holes cannot decrease. This is the generalized second law--GSL for short.” https://lnkd.in/draqjTW View in LinkedIn

VIOLATION. “The GSL has passed a large number of stringent, if purely theoretical, tests. When a star collapses to form a black hole, the black hole entropy greatly exceeds the star's entropy. In 1974 Hawking demonstrated that a black hole spontaneously emits thermal radiation, now known as Hawking radiation, by a quantum process.” (GSL = generalized second law). https://lnkd.in/draqjTW View in LinkedIn

THE SOLUTION. “The Christodoulou-Hawking theorem fails in the face of this phenomenon (the mass of the black hole, and therefore its horizon area, decreases), but the GSL copes with it: the entropy of the emergent radiation more than compensates for the decrement in black hole entropy, so the GSL is preserved.” (GSL = generalized second law). https://lnkd.in/draqjTW View in LinkedIn

HISTORY. “In 1986 Rafael D. Sorkin of Syracuse University exploited the horizon's role in barring information inside the black hole from influencing affairs outside to show that the GSL (or something very similar to it) must be valid for any conceivable process that black holes undergo. His deep argument makes it clear that the entropy entering the GSL is that calculated down to level X, whatever that level may be.” (GSL = generalized second law). https://lnkd.in/draqjTW View in LinkedIn

SORKIN’S EQUIVALENCE. “Hawking's radiation process allowed him to determine the proportionality constant between black hole entropy and horizon area: black hole entropy is precisely one quarter of the event horizon's area measured in Planck areas. (The Planck length, about 10(33) centimeter, is the fundamental length scale related to gravity and quantum mechanics. The Planck area is its square.) https://lnkd.in/draqjTW View in LinkedIn

PLANCK LENGTH: 1.6 × 10-33 centimeters View in LinkedIn

PHENOMENA VS CONSCIOUSNESS. “All things in the world, as we normally experience them, are phenomena, beneath or behind which lies their “being-in-itself”. Consciousness, by contrast, has “being-for-itself”, since each consciousness is not only a consciousness-of-its-object but also a pre-reflective consciousness-of-itself (conscience de soi).” (A wonderful review of phenomenology) https://lnkd.in/dFHYwFQ View in LinkedIn

A typical dusty, chaotic stonemason’s workship in La Bisbal d’Emporda, Catalonia. View in LinkedIn

SORKIN’S PREDICTION. “Even in thermodynamic terms, this is a vast quantity of entropy. The entropy of a black hole one centimeter in diameter would be about 10(66) bits, roughly equal to the thermodynamic entropy of a cube of water 10 billion kilometers on a side.” https://lnkd.in/draqjTW View in LinkedIn