Tunneling, the Quillen metric and analytic torsion for high powers of a holomorphic line bundle
Robert J. Berman
TL;DR
The work analyzes tunneling phenomena in the asymptotic Dolbeault complex for high tensor powers $kL$ of an ample line bundle. By combining Bergman kernel asymptotics with variational identities, it derives a precise large-$k$ description of truncated analytic torsions and the Quillen determinant, showing that their limits are governed by the pluripotential energy $\mathcal{E}(P\phi_L,\phi_L)$ and that exponentially small eigenvalues necessarily appear when this energy is nonzero. The results provide a new proof of Quillen metric asymptotics in a non-Kähler setting and connect spectral tunneling to determinant-line geometry, with parallels drawn to Witten Laplacians and large deviation principles for fermions. The paper also discusses the distinction between small and exponentially small eigenvalues and outlines conjectures about limiting measures and localization phenomena in the Dolbeault context, offering a roadmap for future investigations in complex geometry and semi-classical analysis.
Abstract
Let L be a line bundle over a compact complex manifold X and endow L and TX with Hermitian metrics. Our main result provides a formula for the average distribution of the exponentially small eigenvalues of the corresponding Dolbeault Laplacians associated to high tensor powers of L; which in physics terminology is a measure of "tunneling" of the Dolbeault complex. Along the way a new proof of the asymptotics of the induced Quillen metric on the corresponding determinant line is obtained. A brief comparison with the tunneling effect for Witten Laplacians and large deviation principles for fermions is also made.
