Theta function

In mathematics, theta functions are special functions of several complex variables. They are important in many areas, including the theories of Abelian varieties and moduli spaces, and of quadratic forms. They have also been applied to soliton theory. When generalized to a Grassmann algebra, they also appear in quantum field theory.

Jacobi's original theta function.

Quotes

• Theta functions pervade all of mathematics ranging from the theory of partial differential equations, mathematical physics, to algebraic geometry, number theory and more recently to representation theory.
  • Maruti Ram Murty (1 January 1993). Theta Functions: From the Classical to the Modern. American Mathematical Society. p. 7. ISBN 978-0-8218-7011-2.