Entropy (disambiguation)

Look up entropy in Wiktionary, the free dictionary.

Additional relevant articles may be found in the following categories:

Thermodynamic entropy
Entropy and information
Quantum mechanical entropy

Entropy, in thermodynamics, is a state function originally introduced to explain why part of a thermodynamic system's total energy is unavailable to do useful work.

Entropy may also refer to:

Thermodynamics

Classical thermodynamic entropy, the original meaning, a state function introduced by Rudolph Clausius to explain why part of a thermodynamic system's total energy is unavailable to do useful work
Gibbs entropy Entropy in classical statistical physics, a measure of disorder, proportional to the logarithm of the number of microstates comprising a macrostate
von Neumann entropy Entropy in quantum statistical physics, the quantum analog of Gibbs entropy

Introductory articles

Entropy (order and disorder) an explanation of what heat and work have to do with disorder
Introduction to entropy an explanation entropy as a measure of irreversibility
Entropy in thermodynamics and information theory an explanation relating the two principal uses of the entropy concept

Other aspects

Entropy and life, research concerning the relationship between the thermodynamic quantity entropy and the evolution of life
Entropy (astrophysics), the adiabatic constant

Information theory and mathematics

Entropy (information theory), also called Shannon entropy, a measure of the unpredictability or information content of a message source.
Algorithmic entropy an (uncomputable) measure of the information content of a particular message.
Rényi entropies, a family of diversity measures generalising Shannon entropy; used to define fractal dimensions.
Measure theoretic entropy, a measure of exponential growth in dynamical systems; equivalent to the rate of increase of Shannon entropy of a trajectory in trajectory-space.
Topological entropy, a measure of exponential growth in dynamical systems; equivalent to the rate of increase of α->0 Renyi entropy of a trajectory in trajectory-space.
Volume entropy, a Riemannian invariant measuring the exponential rate of volume growth of a Riemannian metric

Other uses in science and technology

Entropy encoding, data compression strategies to produce a code length equal to the entropy of a message
Entropy (computing), an indicator of the number of random bits available to seed cryptography systems
Entropy (anesthesiology), a measure of a patient's cortical function, based on the mathematical entropy of EEG signals
Entropy (ecology), measures of biodiversity in the study of biological ecology, based on Shannon and Rényi entropies
Social entropy, a measure of the natural decay within a social system

Media

Film and television

Entropy (film), a 1999 film by Phil Joanou
"Entropy" (Buffy episode)

Games

Entropy (1977 board game)
Entropy (1994 board game)
Entropy (video game)
Entropy or Alchemiss, a character in Freedom Force vs the 3rd Reich

Literature

Entropy: A New World View, a book by Jeremy Rifkin and Ted Howard
"Entropy", a 1960 short story by Thomas Pynchon
"Entropy", a 1995 short story by Leanne Frahm

Music

Entropy (album), an album by Anathallo and Javelins
Entropy / Send Them, an EP by DJ Shadow and the Groove Robbers
"Entropy", a song by Bad Religion from Against the Grain
"Entropy", a song by VNV Nation from Matter + Form
"Entropy", a song by Moxy Früvous from The 'b' Album
"Entropy", a song by MC Hawking

Software

Entropy (package manager), a Sabayon Linux package manager
Entropy (anonymous data store), a discontinued project to build a computer network designed to be resistant to censorship