Glossary

Electromagnetism
  • nonpermeable - same magnetic permeability as free space
  • grounded - potential fixed at zero
  • plasma frequency - resonant frequency of electron oscillations in a plasma
  • invariant mass -
  • relativistic mass - E/c^2
    Quantum Mechanics
  • classical spins - can only be up or down
  • local potential - velocity independent (Abers' definition)
  • central potential - spherically symmetric
  • attractive potential - always less than value at infinity
  • singlet state - total spin is zero
  • triplet state - total spin is one
  • dipole transition - component of vector in the matrix element
  • c-number - commutes like scalars (Shankar page 54)
  • q-number - non-commuting like operators (Shankar page 54)
  • exchange force - apparent force due to Pauli exclusion
    Thermodynamics
  • integrals of motion - constants of motion
  • diathermal - heat conductor
  • adiabatic - heat insulator
  • quasistatic - stays infinitesimally close to equilibrium
  • ideal gas - non-interacting particles
  • degenerate gas - obeys FD or BE statistics
  • thermodynamic equilibrium - mechanical, thermal, and chemical equilibrium
  • kinetic theory - detailed study of particle interactions
  • statistical weight - parameter of ln in conventional definition of entropy
  • occupancy - particles-per-quantum-state function
  • dispersion relation - relation between energy and momentum
  • boltzmann factor - canonical weighting factor
  • equation of state
  • intensive parameter
  • extensive parameter
  • internal parameter
  • external parameter
  • microscopic parameter
  • macroscopic parameter
  • classical regime
    Classical Mechanics
  • virial - a certain function relating to a system of forces and their points of application, first used by Clausius in the investigation of problems in molecular physics. Etymology: Latin expression vis, viris, force. Source: Webster's Revised Unabridged Dictionary (1913).
  • elastic collision - collision in which kinetic energy is conserved
  • inelastic collision of the first kind (endoergic collision) - collision in which kinetic energy is lost
  • inelastic collision of the second kind (superelastic collision, exoergic collision) - collision in which kinetic energy is gained
    Particle Physics
  • scalar particle - particle of spin zero
  • vector particle - particle of non-zero spin
  • fermion - a particle with half integer spin
  • boson - a particle with integer spin
  • gauge boson - a boson that acts as a mediator of a fundamental interaction
  • Majorana fermion - a fermion that is its own anti-particle
  • Dirac fermion - a fermion that is not its own anti-particle
  • valence quark - a quark which imparts quantum numbers onto a hadron
  • sea quark - a virtual quark in a hadron that does not contribute to the hadron's quantum number
  • lepton universality - the couplings of the leptons to gauge bosons are flavor-independent
    Mathematics
  • power law - variable to a constant power