Physics: bra-ket\ev

\evCommand

Used in quantum mechanics to denote expectation values of operators

\ev{A}
Available in
physics
Kind
prefix
Allowed mode
math
Frequency
Not measured
Commonality
medium
Renderer support
PackageMathJaxKaTeXXeTeX
physicsMathJax: FullKaTeX: NoneXeTeX: Full
About the test scope

Syntax#

\evs*stars*starm{a}math contentg{b}optional math content

Argspec s s m g — three optional and one mandatory argument. Reading argspecs

Examples#

\ev*{A}
\ev**{A}
\ev{A}{B}
\ev**{A}{B}

In TeXForm#

TeXForm parses this entry as prefix syntax; the package determines its argument specification.

Expands to#

\ev{#1}{#2} \left\langle{#2}\right\vert{#1}\left\vert{#2}\right\rangle

Depends on star modifiers. If no second argument, it's just \langle{#1}\rangle.

physics/expectation-expandfrom Faithfulrender

Expand expectation-value helpers to explicit angle brackets.

\ev{#1} \left\langle #1 \right\rangle

Equivalent forms#

  • \expectationvalue{A}exact

    Long form of \ev

  • \expval{A}exact

    Alternative short alias

See also#

Test cases#

physics
InputCaseMathJaxKaTeXXeTeX
\ev{a}Positive · baselinePassFailPass
\ev*{a}Positive · vary:s[0]PassFailPass
\ev{a}{b}Positive · vary:g[3]PassFailPass
\ev**{a}{b}Positive · maximalPassFailPass
\ev aPositive · bare[2]PassFailPass
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