David Finkelstein was the first, in 1958, who identified Schwarzschild's solution of the Einstein field equations as corresponding to a region in space from which nothing escapes.[4][5] In 1959, Finkelstein and Charles W. Misner found the gravitational kink, a topological defect in the gravitational metric, whose quantum theory could exhibit spin 1/2.[6] The simplest kink exhibited an easily understood event horizon that led him to recognize the one in the Schwarzschild metric and eliminate its coordinate singularity. In essence, Finkelstein determined that whatever falls past the Schwarzschild radius into a black hole cannot escape it; the membrane is one-directional. This important work influenced the decisions of Roger Penrose and John Archibald Wheeler to accept the physical existence of event horizons and black holes.[7]
Most of Finkelstein's work is directed toward a quantum theory of space-time structure. He early on accepted the conclusion of John von Neumann that anomalies of quantum mechanical measurement are anomalies of the logic of quantum mechanical systems. Therefore, he formed quantum analogues of set theory, the standard language for classical space-time structures, and proposed that space-time is a quantum set of space-time quanta dubbed "chronons", a form of quantum computer with spins for quantum bits, as a quantum version of the cellular automaton of von Neumann. His early quantum space-times proving unphysical, he later studied chronons with a regularized form of Bose–Einstein statistics due to Tchavdar D. Palev.[8]
Influenced by his discussions of Buddhistphilosophy at the Mind and Life dialogues, Finkelstein developed a philosophical theory of "universal relativity" which he thought might help advance physics. According to Finkelstein:[15]
The Buddhist principle that all is empty is understood by some as the principle that all is relative (Thurman 1993). This universal relativity principle is more embracing though less structured than Einstein’s general relativity principle, which still admits many absolutes. The major changes in physics in this century have been extensions of relativity at one level or another, and I think a further extension is due, at an even deeper level of physics than the previous. Philosophical inquiry has aided such extensions before, and it could do so again. A philosophical argument for a universal relativity could be a useful guide for future physics.
^Finkelstein, David; Powell, James R. (1970). "Ball Lightning: Less well known than stroke lightning, ball lightning is about as frequent and can be simulated in the laboratory". American Scientist. 58 (3): 262–280. JSTOR27829081.
