|Rendition of the side view of a black hole, predicted to exist in 1915 by American mathematical physicist William Sidis, showing Hawking radiation shooting out the sides, as was predicted to exist in 1974 by British astrophysicist Stephen Hawking, following earlier circa 1970 discussion between American theoretical physicist John Wheeler, coiner of the term “black hole” (1967), and his graduate student Mexican-born Jewish physicist Jacob Bekenstein as whether or not black holes flout the second law of thermodynamics. |
Sidis | Black body stars
In 1920, American mathematical astrophysicist William Sidis, at the age of seventeen, was the first to predict the existence of black holes or "black body stars", as he called them, into which all light and radiant energy would fall, thus making the star totally invisible, being volumetrically delineated by what he termed a "boundary surface", using terminology from classical thermodynamics and black body or radiation thermodynamics.  Numerous references now credit Sidis as the first to publish on this topic; although, to note, it seems his work was relatively unknown to academia until the 1970s.  As American philosopher Frank Magill put it in 1992: “Sidis had successfully predicted the existence of black holes at a time when no one had even dreamed of such things.” 
Sidis wrote out the theory in 1920, while curiously being locked in an asylum, eventually to be published in the 1925 book The Animate and the Inanimate. The book, supposedly, remained essentially lost to academia until found in an attic in circa 1978 by biographer Daniel Mahony and given to Sidis' old Harvard classmate Buckminster Fuller who after reading it in 1979 sent in a letter Scientific America extolling the work suggesting that it be reprinted. On black holes, Fuller comments:  “Imagine my excitement and joy on being handed this Xerox of Sidis’ 1925 book, in which he clearly predicts the black hole.” 
The next person to suggest the existence of black holes, according to biographer Amy Wallace, was Indian-born American astrophysicist Subrahmanyan Chandrasekhar as discussed in his the 1939 book An Introduction to the Study of Stellar Structure, in which he applies the newly invented 1908 axiomatic thermodynamics of Greek mathematician Constantin Caratheodory to the study of black holes viewed as abstract thermodynamic systems.  The term "black hole" was coined in 1967 by American theoretical physicist John Wheeler to describe this theoretical black star-space region phenomenon. 
Black hole thermodynamics
See main: Black hole thermodynamicsThe first ideas as to what happens to the lost information or energy-matter falling into a black hole, in the context of entropy increase, traces to early 1970s discussions between Wheeler and his graduate student Mexican-born Jewish physicist Jacob Bekenstein. In 1971, Wheeler pointed out to Bekenstein that black holes seem to flout the second law of thermodynamics.  In 1972, to remedy this issue, Bekenstein suggested that black holes should have a well-defined entropy and went on to formulate a generalized second law of black hole thermodynamics which states that “the sum of black hole entropy and ordinary entropy outside a black hole never decreases.” To find and measure this “black hole entropy”, Bekenstein reasoned that, because of the effect that the massive gravity of black holes pulls light, energy, and matter into its body, according to German-born American Albert Einstein’s mass-energy relation E=mc², a black hole's entropy increase must be proportional or related to its surface area.
Two years later, in 1974, Beckenstein's postulate was confirmed when British astrophysicist Stephen Hawking discovered that black holes radiate energy, now called Hawking radiation, and hence they must have a correlative temperature and thus an entropy (black hole entropy). 
1. (a) Sidis, William J. (1920). The Animate and the Inanimate (ch. 8: Stellar Hypothesis). Publisher: R.G. Badger, 1925.
(b) Wallace, Amy. (1986). The Prodigy: a Biography of William James Sidis: America's Greatest Child Prodigy (black holes, pg. 157; Dan Mahony, pgs. 157, 188-89). Dutton Adult.
2. (a) Fuller, R. Buckminster. (1979). "Letter to Gerard Piel: on Sidis' book The Animate and the Inanimate", Scientific American, Feb 27.
(b) Dan Mahony: what have you to do with all this? - FAQs about W.J. Sidis - DanMahony.com.
3. Chandrasekhar, Subrahmanyan. (1939). An Introduction to the Study of Stellar Structure (ch. 1: The Laws of Thermodynamics, pgs. 11-37). University of Chicago Press.
4. Fabbri, Alessandro and Navarro-Salas, Jose. (2005). Modeling Black Hole Evaporation (pg. 17). Imperial College Press.
5. Wald, Robert M. (1994). Quantum Field Theory in Curved Spacetime and Blackhole Thermodynamics. Chicago: The University of Chicago Press.
6. Baeyer, Hans Christian von. (2004). Information - the New Language of Science. Cambridge, (pgs. 205-11). Massachusetts: Harvard University Press.
7. Daintith, John. (2005). Oxford Dictionary of Physics. Oxford University Press.
8. (a) Conway, Flo and Siegelman, Jim. (2006). Dark Hero of the Information Age: in Search of Norbert Wiener (William Sidis on black holes, pg. 335). Basic Books.
(b) Lyons, Viktoria and Fitzgerald, Michael. (2005). Asperger Syndrome: a Gift or a Curse? (Quote: “In his major work on cosmology The Animate and the Inanimate, Sidis predicted antimatter and black holes, collapsed stars so heavy and dense that their high gravity prevents even light from escaping, fourteen years before the first publication by Subrahmanyan Chandrasekhar”, pg. 164). Nova Publisher.
9. Magill, Frank N. (1992). Magill’s Literary Annual, Volume 1 (Quote, pg. 442). Salem Press.
● Black hole – Wikipedia.