Toric K\"ahler metrics seen from infinity, quantization and compact tropical amoebas

TL;DR

This paper explores the limits of toric K"ahler metrics, their quantization, and degenerations, revealing connections between geometric quantizations, tropical amoebas, and the interplay of complex and tropical geometry.

Contribution

It introduces a new perspective on the degeneration of toric K"ahler metrics and their quantizations, linking them to tropical amoebas and providing a bridge between complex and tropical geometry.

Findings

Holomorphic sections converge to Dirac delta distributions on Bohr-Sommerfeld fibers.

Toric metric degenerations describe limits of hypersurface amoebas via tropical amoebas.

Continuous interpolation between geometric quantizations in different polarizations.

Abstract

We consider the metric space of all toric K\"ahler metrics on a compact toric manifold; when "looking at it from infinity" (following Gromov), we obtain the tangent cone at infinity, which is parametrized by equivalence classes of complete geodesics. In the present paper, we study the associated limit for the family of metrics on the toric variety, its quantization, and degeneration of generic divisors. The limits of the corresponding K\"ahler polarizations become degenerate along the Lagrangian fibration defined by the moment map. This allows us to interpolate continuously between geometric quantizations in the holomorphic and real polarizations and show that the monomial holomorphic sections of the prequantum bundle converge to Dirac delta distributions supported on Bohr-Sommerfeld fibers. In the second part, we use these families of toric metric degenerations to study the limit of compact hypersurface amoebas and show that in Legendre transformed variables they are described by tropical amoebas. We believe that our approach gives a different, complementary, perspective on the relation between complex algebraic geometry and tropical geometry.