This article is about the letter of the Greek alphabet. For the irrational iota phi theta probate found in nature, see Golden ratio. 21st letter of the Greek alphabet. Phi is also used as a symbol for the golden ratio and on other occasions in math and science.
This use is separately encoded as the Unicode glyph ϕ. Especially: The argument of a complex number. The phase of a wave in signal processing. Internal or effective angle of friction.
The work function of a surface, in solid-state physics. A shorthand representation for an aromatic functional group in organic chemistry. The ratio of free energy destabilizations of protein mutants in phi value analysis. In cartography, geodesy and navigation, latitude.
The ratio between the actual fuel air ratio to the stoichiometric fuel air ratio. In economics, this is usually an additive term. In flight dynamics, the roll angle. In philosophy, φ is often used as shorthand for a generic act. In perceptual psychology, the phi phenomenon is the apparent motion caused by the successive viewing of stationary objects, such as the frames of a motion picture.
In lexical-functional grammar, the function that maps elements from the c-structure to the f-structure. In ecology, site survival probability, or the probability that a species will continue to occupy a site if it was there the previous year. The logo of La France Insoumise, a French political party. The magnetic flux and electric flux in physics, with subscripts distinguishing the two. The cumulative distribution function of the normal distribution in mathematics and statistics.
In philosophy, Φ is often used as shorthand for a generic act. The number of phases in a power system in electrical engineering, for example 1Φ for single phase, 3Φ for three phase. A common symbol for the parametrization of a surface in vector calculus. Used in mathematical and technical contexts. Because Unicode represents a character in an abstract way, the choice between glyphs is purely a matter of font design.
03D5 GREEK PHI SYMBOL is designed for this function. 0278, LATIN SMALL LETTER PHI, because in this use only the stroked glyph is considered correct. It typically appears in a form adapted to a Latin typographic environment, with a more upright shape than normal Greek letters and with serifs at the top and bottom. Look up Φ, φ, or phi in Wiktionary, the free dictionary. The Da Vinci Code and the Criminal Minds episode, “Masterpiece”. An introductory dictionary of Lacanian psychoanalysis.