Psi function

Psi function can refer, in mathematics, to

• the ordinal collapsing function ${\displaystyle \psi (\alpha )}$
• the Dedekind psi function ${\displaystyle \psi (n)}$
• the Chebyshev function ${\displaystyle \psi (x)}$
• the polygamma function ${\displaystyle \psi ^{m}(z)}$or its special cases
  • the digamma function ${\displaystyle \psi (z)}$
  • the trigamma function ${\displaystyle \psi ^{1}(z)}$

and in physics to

• the quantum mechanical wave function.