Ψ

Psi (ψ) | (/(p)saɪ/; uppercase Ψ, lowercase ψ) The 23rd letter of the Greek Alphabet with a numeric value of 700. In both Classical and Modern Greek, the letter indicates the combination /ps/ (as in English word "lapse"). The letter is most commonly used in quantum mechanics for wave functions like the ‘Schrödinger Equation’. May also be used to represent a position of a qubit in a quantum computer. It is also used in the Polygamma Function where ‘Γ’ (z) is the gamma function. Other notable appearances of ‘Psi’ include: - Psychology/Psychiatry/Parapsychology (sometimes). - Water Potential (Biology - Osmosis). - Biochemistry: the rare nucleotide ‘Pseudouridine’. - The gas giant ‘Neptune’ (eighth planet). - The J/ψ meson, in particle physics. - ‘Sai’ (weapon), the name of which is pronounced the same way - it also has the general shape of ψ. - Stream function in fluid mechanics defining the curve to which the flow velocity is always tangent. (note: some values may need citation)