Entropy is a fundamental scientific concept that quantifies the statistical probability of a system's state. It is a universal measure of multiplicity.

Entropy may also refer to:

Science and technology

Physics

  • Entropy (classical thermodynamics), thermodynamic entropy in macroscopic terms, with less emphasis on the statistical explanation
  • Entropy (statistical thermodynamics), the statistical explanation of thermodynamic entropy based on probability theory
  • Configuration entropy, the entropy change due to a change in the knowledge of the position of particles, rather than their momentum
  • Conformational entropy, the entropy change due to a change in the "configuration" of a particle (e.g. a right-handed vs. a left-handed polyatomic molecule)
  • Tsallis entropy, a generalization of Boltzmann-Gibbs entropy
  • von Neumann entropy, entropy in quantum statistical physics and quantum information science
  • Entropy (order and disorder), the relationship of disorder with heat and work
  • Entropy in thermodynamics and information theory, the relationship between thermodynamic entropy and information (Shannon) entropy
  • Entropy (energy dispersal), dispersal of energy as a descriptor of entropy
  • 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
  • Differential entropy, a generalization of Entropy (information theory) to continuous random variables
  • Entropy of entanglement, related to the Shannon and von Neumann entropies for entangled systems; reflecting the degree of entanglement of subsystems
  • Algorithmic entropy an (incomputable) measure of the information content of a particular message
  • Rényi entropy, a family of diversity measures generalising Shannon entropy; used to define fractal dimensions
  • 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
  • Graph entropy, a measure of the information rate achievable by communicating symbols over a channel in which certain pairs of values may be confused

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

Arts and entertainment

Film and television

  • Entropy (film), a 1999 film by Phil Joanou
  • "Entropy" (Buffy episode), 2002
  • "Entropy", an episode of Criminal Minds season 11

Games

  • Entropy (board game)
  • Entropy (video game)
  • Entropy or Alchemiss, a character in Freedom Force vs the 3rd Reich
  • N. Tropy, a character from Crash Bandicoot: Warped
  • Entropy: Zero, a Source mod for Half-Life 2 released in 2017 developed by Breadman
  • Entropy: Zero 2, a sequel to Entropy: Zero released in 2022
  • Entropy: Zero - Uprising, a mod of Entropy: Zero developed by Employee8 and Filipad

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
  • Entropy (journal), a scientific journal published by MDPI
  • Entropy (magazine), an online literary magazine

Music

  • Entropy, a 2005 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 Kelly Osbourne from Sleeping in the Nothing
  • "Entropy", a song by VNV Nation from Matter + Form
  • "Entropy", a song by Moxy Früvous from The 'b' Album
  • "Entropy", a song by Brymo from Oṣó
  • "Entropy", a song by Daniel Caesar from Case Study 01
  • "Entropy", a song by Beach Bunny from Emotional Creature
  • "Entropy", a song by MC Hawking
  • "Entropy", a song by Grimes and Bleachers
  • Entropia (album), an album by Pain of Salvation
  • Entropy, a track by Nigel Stanford
  • The Book Of Us: Entropy, an album by DAY6

Other uses in arts and entertainment

  • Entropy (choreography), the difference between a transcription and a performance

Other uses

  • Entropy (package manager), a Sabayon Linux utility
  • Exluna Entropy, computer graphics rendering software
  • Information entropy, relating to disruptive actions taken in Internet vigilantism

See also