The zeta function of a mathematical operator
The zeta function may also be expressible as a spectral zeta function[1] in terms of the eigenvalues
by It is used in giving a rigorous definition to the functional determinant of an operator, which is given by
The Minakshisundaram–Pleijel zeta function is an example, when the operator is the Laplacian of a compact Riemannian manifold.
One of the most important motivations for Arakelov theory is the zeta functions for operators with the method of heat kernels generalized algebro-geometrically.