Coherent mathematical framework for the Feynman path integral in physically relevant QFT
Establish a coherent mathematical framework for the Feynman path integral applicable to physically relevant quantum field theories, particularly in curved spacetimes, thereby reconciling geometric approaches with rigorous measure-theoretic formulations.
References
In order to reconcile the geometric point of view with the subject of QFT, the main problem to address is the description, in a coherent mathematical framework, of the Feynman path integral. Even though this problem has been a well-known subject of study for many years [GJ87, Car&97, DCF97, Wes03, CD06], it is still unclear how to proceed for the physically relevant cases.
— Geometric Flavours of Quantum Field Theory on a Cauchy Hypersurface: Gaussian Analysis for the Hamiltonian Formalism and Applications to Cosmology
(2502.12760 - MartÃnez-Crespo, 18 Feb 2025) in Chapter 1, Section 1.1