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Masses and springs. Systems with infinite degrees of freedom can have properties entirely different from those we expect from examining their finite counterparts. In the Newtonian case, they display both indeterminism and violations of energy and momentum conservation. These supertasks systems continue a tradition of puzzlement that was initiated by Zeno in antiquity. I have examined many aspects of these supertasks systems in classical and relativistic physics in papers with John Earman. I also set up a supertask system in quantum theory and found that, while there were some pathologies, they turned out to be better behaved than classical supertasks. With J. Earman, "Forever is a Day: Supertasks in Pitowsky and Malament-Hogarth Spacetimes," Philosophy of Science, 60 (1993), 22-42. Download

With John Earman, "Infinite Pains: The Trouble with Supertasks," in A. Morton and S. Stich (eds.) Benacerraf and his Critics (Cambridge, MA: Blackwells, 1996) pp.231-261. Download

With John Earman "Comments on Laraudogoitia's 'Classical Dynamics, Indeterminism and a Supertask," British Journal for the Philosophy of Science, 49 (1998), pp.123-33. Download

"A Quantum Mechanical Supertask" Foundations of Physics, 29, pp. 1265-1302. Download

With Joseph S. Alper, Mark Bridger and John Earman, "What is a Newtonian System? The Failure of Energy Conservation and Determinism in Supertasks," Synthese, 124(2000), pp. 281-293. Download
Because of the specific shape of the dome at its apex, Newton's equations of motion tell us that a mass at rest at the apex can spontaneously be set into motion. It has been suggested that this indeterminism should be discounted since it draws on an incomplete rendering of Newtonian physics; or it is "unphysical"; or it employs illicit idealizations. I analyze and reject each of these reasons. "The Dome: An Unexpectedly Simple Failure of Determinism," download.
See also "The Dome: A Simple Violation of Determinism in Newtonian Mechanics" in Goodies.
Szilard's one molecule engine. Maxwell's demon is a fictitious, miniscule being imagined by Maxwell as able to reverse the second law of thermodynamics by manipulating individual molecules. In a tradition of work initiated by Szilard in the 1920s, it has become standard to predict the failure of the demon on information theoretic grounds through a connection supposed to obtain between information processing and entropy dissipation. In a study with John Earman, we have suggested that this account of the demon's failure is either based on question begging or groundless supposition. With John Earman, "Exorcist XIV: The Wrath of Maxwell's Demon." Studies in the History and Philosophy of Modern Physics, Part I "From Maxwell to Szilard" 29(1998), pp.435-471; Part II: "From Szilard to Landauer and Beyond," 30(1999), pp.1-40. Download.

The present orthodoxy holds that Maxwell's demon must fail to reverse the second law of thermodynamics because of a hidden entropy cost in the erasure of information. The analysis is based on Landauer's principle, which asserts that the erasure of n bits of information is accompanied by the passage of least k ln n of entropy to the surroundings. I argue that Landauer's principle is based on the formation of illicit canonical ensembles in statistical physics that give the illusion of the necessity of this entropy cost. I also urge that, even if the principle were correct, the literarure seeks to establish that it must defeat all Maxwell demons by the inadquate means of merely displaying a few suggestive examples.

 "Eaters of the Lotus: Landauer's Principle and the Return of Maxwell's Demon." 36 (2005), pp. 375-411. Download