Irreversibility and heat generation in the computing process

IBM Journal of Research and Development

Volumn 44, Issue 1, 2000, Pages 261-269

  Landauer, Rolf ^a  

^a NONE

Author keywords

[No Author keywords available]

Indexed keywords

ERROR ANALYSIS; FORMAL LOGIC; HEAT LOSSES; MATHEMATICAL MODELS; THERMAL EFFECTS;

LOGICAL IRREVERSIBILITY;

COMPUTATIONAL METHODS;

EID: 0033705343     PISSN: 00188646     EISSN: None     Source Type: Journal    
DOI: 10.1147/rd.441.0261     Document Type: Article

References (8)

1. L. Brillouin, Science and Information Theory, Academic Press Inc., New York, New York, 1956.
2. R. Landauer and J. A. Swanson, Phys. Rev., 121, 1668 (1961).
3. K. Mendelssohn, Progress in Cyrogenics, Vol. 1, Academic Press Inc., New York, New York, 1959. Chapter I by D. R. Young, p. 1.
4. L. B. Russell, IRE Convention Record, p. 106 (1957).
5. J. A. Swanson, IBM Journal, 4, 305 (1960). We would like to take this opportunity to amplify two points in Swanson's paper which perhaps were not adequately stressed in the published version. (1) The large number of particles (∼100) in the optimum element are a result of the small energies per particle (or cell) involved in the typical cooperative phenomenon used in computer storage. There is no question that information can be stored in the position of a single particle, at room temperature, if the activation energy for its motion is sufficiently large (∼ several electron volts). (2) Swanson's optimum volume is, generally, not very different from the common sense requirement on U, namely: vt exp(-U/kT)<1, which would be found without the use of information theory. This indicates that the use of redundancy and complicated coding methods does not permit much additional information to be stored. It is obviously preferable to eliminate these complications, since by making each element only slightly larger than the "optimum" value, the element becomes reliable enough to carry information without the use of redundancy.
6. R. L. Wigington, Proceedings of the IRE, 47, 516 (1959).
7. A. W. Lo, Paper to appear in IRE Transactions on Electronic Computers.
8. D. Hibert and W. Ackermann, Principles of Mathematical Logic, Chelsea Publishing Co., New York, 1950, p. 10.