Physics
The physics of information
Information is not abstract: storing, copying and erasing it has physical consequences. These references chart the link between information and thermodynamics — from Landauer's bound and Maxwell's demon to the unitarity that makes closed quantum systems reversible.
Landauer's principle →
Erasing one bit of information must dissipate at least kT ln 2 of heat to the surroundings.
Wikipedia · concept
Irreversibility and Heat Generation in the Computing Process →
The original paper establishing that logically irreversible operations carry a minimum heat cost.
R. Landauer · IBM J. R&D 5(3) · 1961
Logical Reversibility of Computation →
Shows that computation discarding no information has no fundamental thermodynamic lower bound.
C. H. Bennett · IBM J. R&D 17(6) · 1973
Maxwell's demon →
The thought experiment linking information and the second law, resolved through the cost of erasure.
Wikipedia · concept
Experimental verification of Landauer's principle… →
A single colloidal particle in an optical trap confirms the kT ln 2 erasure bound in the laboratory.
A. Bérut et al. · Nature 483 · 2012
Unitarity (quantum reversibility) →
Closed-system quantum evolution is information-preserving and reversible — the quantum face of reversibility.
Wikipedia · concept
Black hole information paradox →
Does black hole evaporation destroy information and break unitarity? A central puzzle of reversibility.
Wikipedia · concept
Landauer's Principle: Past, Present and Future →
A recent review surveying the theory, experiments and open questions around the information–heat bound.
review · 2025
The link to computing
The same kT ln 2 bound that connects information to heat here underlies the case for reversible computing. See the Programming principles, where avoiding erasure is what lets computation approach zero energy.