Psi (letter) (generalized) positional states of a qubit in a quantum computer. Psi is also used as the symbol for the polygamma function, defined by where formula_3 is the gamma function. The letters Ψ or ψ can also be a symbol for: These characters are used only as mathematical symbols. Stylized Greek text should be encoded using the normal Greek letters, with markup and formatting to indicate text style. Psi (letter) Psi (; uppercase ', lowercase '; "psi" ) is the 23rd letter of the Greek alphabet and has a numeric value of 700. In both Classical and Modern Greek, the letter
History of the Greek alphabet Greek. Since the names of the letters "’āleph" and "hē" were pronounced and by the Greeks, with initial vowels due to the silent gutturals (the disambiguation "e psilon" "narrow e" came later), the acrophonic principle was retained for vowels as well as consonants by using them for the Greek vowel sounds and . Only the letter "‘ayin" for necessitated a change of name ("o", later "o micron"). Phoenician also had an "emphatic" consonant, "ṭēth", which did not exist in Greek. However, Greek had an aspiration distinction that Phoenician lacked, and used ṭēth for the aspirated . The Phoenician consonants "kaph"