An Etymological Dictionary of Astronomy and Astrophysics
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Paul A. M. Dirac (1902-1984), English theoretical → physicist, one of the founders of → quantum mechanics and → quantum electrodynamics, Nobel Prize for Physics in 1933. → Dirac annihilation, → Dirac equation, → Dirac function, → Dirac constant, → Fermi-Dirac statistics .

Same as → pair annihilation.

→ Dirac; → annihilation.

The → Planck constant divided by 2π and denoted ħ, pronounced h-bar. Also called → reduced Planck constant.

→ Dirac; → constant.

The equation that describes the behavior of an → electron in a way that combines the requirements of → quantum mechanics with the requirements of → special relativity. The Dirac equation predicted the existence of antimatter

→ Dirac; → equation.

A function of x defined as being zero for all values of x other than x = x₀ and having the definite integral from x = -∞ to x = +∞ equal to unity.

→ Dirac; → function

→ Dirac constant.

→ Dirac; → constant.

The statistical distribution of → fermions over the energy states for a system in → thermodynamic equilibrium. In other words, the probability that a given energy level be occupied by a fermion.

→ fermi, → Dirac function; → statistics.