Free energy

Free energy may refer to:

In science:

• Thermodynamic free energy, the energy in a physical system that can be converted to do work, in particular:
  • Helmholtz free energy (A=U–TS), the energy that can be converted into work at a constant temperature and volume
    • Work content, a related concept used in chemistry
  • Gibbs free energy (G=H–TS), the energy that can be converted into work at a constant temperature and pressure throughout a system
• Variational free energy, a construct from information theory that is used in variational Bayesian methods

In economics:

• Energy from sources that do not require an input which has to be paid for, (usually a sub-set of renewable energy)

In pseudoscience:

• Free energy device, a hypothetical perpetual motion device that creates energy, thereby contradicting the laws of thermodynamics

In popular culture:

• Free energy suppression, a conspiracy theory that advanced energy technologies are being suppressed by governments and/or special interest groups

In music:

• Free Energy (band), a 5-piece rock band on DFA Records

See also

• Free-energy relationship - a relation between the reaction rate or equilibrium constants of two series of chemical reactions
• Free energy perturbation - a method based on statistical mechanics that is used in computational chemistry for computing free energy differences
• Free energy principle - a variational formulation of self-organisation in biological systems, applied in particular to neuroscience
• Principle of minimum energy - a thermodynamic formulation based on the second law