\varphi
The symbol \varphi is a Greek letter used in mathematics and science to represent various concepts, such as the golden ratio, angles, or phases in physics. It is often used interchangeably with \phi, though \varphi typically refers to the variant form of the letter.
Represents the golden ratio, a mathematical constant.
\varphi = \frac{1 + \sqrt{5}}{2}
Used to denote an angle in geometry or trigonometry.
\theta = \varphi + \alpha
Represents a phase in wave equations or quantum mechanics.
\varphi(t) = \varphi_0 e^{-i\omega t}