Rolf Landauer
contemporaryPhilosophy of Physics / Information Theory1927 – 1999
Rolf Landauer (1927–1999) was an IBM Research physicist whose work established foundational connections between information theory and thermodynamics. He is best known for Landauer's principle, which holds that logically irreversible operations—such as erasing a bit of information—must dissipate a minimum quantity of energy as heat. His insight that 'information is physical' profoundly influenced both the physics of computation and debates about Maxwell's Demon.
Notable Achievements
1
Formulated Landauer's principle: logical irreversibility implies physical entropy increase
2
Established that erasing one bit of information dissipates at least kT ln 2 of energy as heat
3
Resolved the Maxwell's Demon paradox by locating the thermodynamic cost in memory erasure, not measurement
4
Pioneered the concept that 'information is physical,' linking computation to physical law
5
Contributed to the theoretical foundations of reversible and quantum computing