- (quantum mechanics) a wavefunction
- (electrical engineering) Electric flux.
Some texts use Ψ (uppercase) for the actual wavefunction that appears in the time-dependent Schrödinger equation, and ψ (=ΨeiEt/ħ) (lowercase) for the time-independent spatial wave function that may exist for stationary states (and which then appears in the time-independent Schrödinger equation), but this distinction is not always observed. Otherwise, the distinction may be made by providing the arguments.
ψ • (ps) (lowercase, uppercase Ψ)
- The lower case letter psi (ψι), the 23rd letter of the modern Greek alphabet.
- ψ΄ (ps΄, “700”)
- ͵ψ (͵ps, “700,000”)
- Appendix:Greek alphabet
- (Greek-script letters) Α α, Β β, Γ γ, Δ δ, Ε ε, Ϝ ϝ, Ͷ ͷ, Ζ ζ, Η η, Ͱ ͱ, Θ θ, Ι ι, Κ κ, Λ λ, Μ μ, Ν ν, Ξ ξ, Ο ο, Π π, Ϻ ϻ, Ϙ ϙ, Ρ ρ, Σ σ ς, Τ τ, Υ υ, Φ φ, Χ χ, Ψ ψ, Ω ω, Ͳ ͳ
- (punctuation) · ﹔
- (diacritics) ᾿ ῾ ´ ` ῀ ¨