The reason is quite simple: there are only so many symbols in the Greek and Latin alphabets, and scientists and mathematicians generally do not use symbols from other languages.
PSI definition: PSI is a unit of pressure expressed in pounds of force per square inch of area. l = 3.6-1 vt, accompanied by text saying, "where l is in meters, v is in kilometers per hour, and t is in seconds" #18 Standard symbols: Standardized quantity symbols are used.

The wavefunction which describes the state of a particle is often denoted by the letter Y (spelled "psi" and pronounced "sigh"). This table explains the meaning of every Letter w symbol. Greek letters are used in mathematics, science, engineering, and other areas where mathematical notation is used as symbols for constants, special functions, and also conventionally for variables representing certain quantities. 1 PSI = 6894 Pascals = 0.070 atmospheres = 51.715 torr We may not know what they are, but they exist with some exact values. 1,099 Views. The letter psi is commonly used in physics to represent wave functions in quantum mechanics, such as in the Schr. This is the atmospheric pressure at sea level. I atm is equal to 101,325 Pascals Hydrostatic pressure (head pressure) Hydrostatic pressure is the pressure due to the weight of a fluid. Greek letters ... Psi symbol as the beginning of a psychology word. The tables below provide you with a list of all the common symbols in maths with meaning and examples on how to read and operate with them. Pounds per square inch (psi) is a unit of pressure most commonly associated with tire pressure for an automobile or bike tire. When you create a presentation for a graduate thesis or dissertation, often, you need to insert Greek letters into the slide. The value of the wave function of a particle at a given point of space and time is related to the likelihood of the particle’s being there at the time. There you have the intensity of diffracted light---analogous to your $|\tilde{\psi}(p)|^2$, but instead of knowing the modulus of $\psi$ everywhere, you know the phase of the analogous thing---the density of scatterers. In one of my courses, some fundamental concepts of Quantum mechanics were needed, so I was going through them when I stumbled upon this. It is a common trap to associate a symbol exclusively with some particular meaning, rather than learning and understanding the physics and relations behind it. Graphical characteristics: Symmetric, Open shape, Monochrome, Contains both straight and curved lines, Has crossing lines. In quantum mechanics a particle has a wavefunction which gives it some probability distributions for position and momentum.
List of common physics notations 5 Other characters Symbol Name Meaning SI Unit of Measure nabla dot the divergence operator often pronounced "del dot" per meter (m−1) nabla cross the curl operator often pronounced "del cross" psi wave function unitless zeta damping ratio unitless. In these contexts, the capital letters and the small letters represent distinct and unrelated entities. Psi 23rd letter Greek alphabet numeric value 700 letter psi commonly used in physics representing wavefunction in quantum Psi greek letter icon, black isolated vector illustration. Specifically, you know the phase is zero, since the density is real. PSI: PSI stands for pounds per square inch. Wave function, in quantum mechanics, variable quantity that mathematically describes the wave characteristics of a particle.