Foundations of Physics Letters

, Volume 16, Issue 1, pp 41–55 | Cite as

A Modified Szilard Engine: Measurement, Information, and Maxwell's Demon

  • Michael Devereux


Using an isolated measurement process, we calculate the effect measurement has on entropy for the multi-cylinder Szilard engine. We find that the system of cylinders possesses an entropy associated with cylinder total energy states, and that it records information transferred at measurement. Contrary to other's results, we find that the apparatus loses entropy due to measurement. The Second Law of Thermodynamics may be preserved if Maxwell's demon gains entropy moving the engine partition.

engine Maxwell's demon quantum measurement information theory 


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Copyright information

© Plenum Publishing Corporation 2003

Authors and Affiliations

  • Michael Devereux
    • 1
  1. 1.Los Alamos Economic Development CorporationLos Alamos

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