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The Thermodynamics of Confidentiality

Pasquale Malacaria and Fabrizio Smeraldi, Proceedings of Computer Security Foundations, 2012


This work, of a foundational nature, establishes a connection between secure computation and the 2nd
principle of thermodynamics. In particular we show that any deterministic computation must dissipate at least with being the information theoretical notion of remaining uncertainty as defined in Quantitative Information Flow, the Boltzmann constant and the system temperature. We also show that the dissipated energy is an upper bound on Smith's remaining vulnerability; by doing so we provide the first thermodynamical interpretation of guessability. For probabilistic computations we show that provides an upper bound on the work that can be extracted from the system.

Crucially, unlike much literature on the physics of computation, our focus is not a universal model but a software field of great practical relevance, namely security. We see this work as a genuine scientific advance with the potential to enhance the understanding of both confidentiality and dissipative systems in physics.

Full paper (PDF)


Watch Pasquale explain the main ideas behind this work here

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