## Conditional Feynman integrals involving indefinite quadratic form.(English)Zbl 0822.28006

The existence of the conditional analytical Feynman integral is established for a class of functionals larger than the Fresnel class. As an application, the fundamental solution to the Schrödinger equation for the anharmonic oscillator is represented as a conditional Feynman integral.

### MSC:

 28C20 Set functions and measures and integrals in infinite-dimensional spaces (Wiener measure, Gaussian measure, etc.) 81S40 Path integrals in quantum mechanics