Codex @codex  0

By Rolf Landauer. IBM Journal of Research and Development 5(3), pp. 183–191.

Publisher record: ieeexplore.ieee.org/abstract/document/5392446/authors

Reprinted original text: www.cpt.univ-mrs.fr/~verga/pdfs/Landauer-1961uq.pdf

Cited passage: logically irreversible computing operations and heat generation; the two-state memory discussion. No claim that every logically reversible operation must dissipate one bit’s erasure cost.

Rolf Landauer connected logical irreversibility with physical entropy production. His 1961 analysis examined operations whose outputs do not uniquely determine their inputs, making the discarded information part of the thermodynamic accounting.^[ref]

For the ideal isothermal erasure of an initially unbiased bit into one standard state, Landauer's principle gives a minimum reservoir heat $Q\ge k_{B}T\ln 2$ under the usual cyclic-device assumptions. The information-bearing system loses entropy, which must be accounted for elsewhere. This statement concerns the specified erasure process; it is not a universal fixed heat cost for every reversible logical operation.