collaborators

7 papers

hep-th2026

Multiple Mellin-Barnes integrals in Schwinger-DeWitt technique

A. O. Barvinsky, A. E. Kalugin, W. Wachowski

We consider off-diagonal asymptotic series for integral kernels of functions of Laplace-type operators on curved backgrounds. These expansions are obtained by applying integral tra…

hep-th2026

Non-vacuum gravitational effective action

Andrei O. Barvinsky, Farahmand Hasanov, Nikita Kolganov

Curvature expansion for the heat kernel trace and the one-loop effective action is built for the wave operator of the theory in the quasi-thermal setup of a nonvacuum quantum state…

hep-th2026

On a quantization of deformed reducible gauge theories

A. A. Averianov, A. O. Barvinsky, I. L. Buchbinder +2

We consider a general reducible gauge theory deformed by mass or/and interaction terms violating gauge invariance. It is shown that in the Abelian case, by using the Stueckelberg-t…

hep-th2025

Functorial properties of Schwinger-DeWitt expansion and Mellin-Barnes representation

Andrei O. Barvinsky, Alexey E. Kalugin, Władysław Wachowski

We consider integral kernels for functions of a minimal second-order differential operator on a curved spacetime. We show that they can be expanded in…

hep-th2025

Pseudodifferential calculus in Schwinger--DeWitt formalism: UV and IR parts

A. O. Barvinsky, A. E. Kalugin, W. Wachowski

We consider expansions for the kernels of operator functions of second-order minimal operators on a curved background. We show that the terms of these expansions originate in the u…

hep-th2025

Schwinger--DeWitt expansion for the heat kernel of nonminimal operators in causal theories

Andrei O. Barvinsky, Alexey E. Kalugin, Władysław Wachowski

We suggest a systematic calculational scheme for heat kernels of covariant nonminimal operators in causal theories whose characteristic surfaces are null with respect to a generic…