Polyakov-Alvarez Formula for Curvilinear Polygonal Domains with Slits
Ellen Krusell
TL;DR
The article extends Polyakov-Alvarez type determinant variation formulas to curvilinear polygonal domains with arbitrary positive corner angles, including slit domains. By deriving a short-time heat-trace expansion via a patchwork approach that aggregates interior, boundary, and corner contributions, it defines the ζ-regularized determinant $\det_\zeta\Delta_{(M,g)}$ for these domains and establishes a conformal variation formula. The main result is a precise Polyakov-Alvarez anomaly formula under smooth conformal changes $g\mapsto e^{2\sigma}g$, with explicit corner-angle corrections, offering a robust tool for analyzing determinants on non-smooth domains. The work connects to random conformal geometry and Loewner energy, and provides analytic machinery applicable to slit and polygonal domains in geometric analysis and mathematical physics.
Abstract
We consider the $ζ$-regularized determinant of the Friedrichs extension of the Dirichlet Laplace-Beltrami operator on curvilinear polygonal domains with corners of arbitrary positive angles. In particular, this includes slit domains. We obtain a short time asymptotic expansion of the heat trace using a classical patchwork method. This allows us to define the $ζ$-regularized determinant of the Laplacian and prove a comparison formula of Polyakov-Alvarez type for a smooth and conformal change of metric.
