Psi function

Psi function can refer, in mathematics, to

• the ordinal collapsing function <math>\psi(\alpha)</math>
• the Dedekind psi function <math>\psi(n)</math>
• the Chebyshev function <math>\psi(x)</math>
• the polygamma function <math>\psi^m(z)</math> or its special cases
• the digamma function <math>\psi(z)</math>
• the trigamma function <math>\psi^1(z)</math>

and in physics to

• the quantum mechanical wave function.