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Dirac Notation

A notation invented by Dirac which is very useful in quantum mechanics. The notation defines the "ket" vector, denoted |psi>, and its conjugate transpose, called the "bra" vector and denoted <psi|. The "bracket" is then defined by <phi|psi>.

Dirac notation satisfies the identities

<phi|O^~|psi>=<phi|O^~psi>
<phi|psi>=int_(-infty)^inftyphi^_psidx,

where psi^_ is the complex conjugate.

See also

Angle Bracket, Bra, Differential k-Form, Ket, L2-Space, One-Form

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Cite this as:

Weisstein, Eric W. "Dirac Notation." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/DiracNotation.html

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