Editing Bra–ket notation (section)

{{short description|Notation for quantum states}}
{{Cleanup reorganize|date=February 2023}}
{{Quantum mechanics|cTopic=Background}}

'''Bra–ket notation''', also called '''Dirac notation''', is a notation for [[linear algebra]] and [[linear operator]]s on [[complex vector space]]s together with their [[dual space]] both in the finite-dimensional and infinite-dimensional case. It is specifically designed to ease the types of calculations that frequently come up in [[quantum mechanics]]. Its use in quantum mechanics is quite widespread.

Bra–ket notation was created by [[Paul Dirac]] in his 1939 publication ''A New Notation for Quantum Mechanics''. The notation was introduced as an easier way to write quantum mechanical expressions.<ref name=Dirac>{{harvnb|Dirac|1939}}</ref> The name comes from the English word "bracket".