\LambdaThe Greek letter Lambda (\Lambda) is used in mathematics and science to represent various concepts, such as eigenvalues in linear algebra, the cosmological constant in physics, and wavelength in physics and engineering.
Diagonal matrix of eigenvalues in linear algebra
\Lambda = \begin{pmatrix} \lambda_1 & 0 \\ 0 & \lambda_2 \end{pmatrix}Einstein's equation with the cosmological constant
E = mc^2 + \LambdaWavelength in terms of Planck's constant and momentum
\Lambda = \frac{h}{p}