Lower bound on the entropy of boundaries and junctions in 1+1d quantum critical systems

TL;DR

This paper establishes a fundamental lower limit on the boundary entropy in 1+1 dimensional quantum critical systems with certain conformal properties, providing new constraints on boundary conditions in these models.

Contribution

It introduces the first general lower bound on the boundary entropy g for bulk critical systems with central charge c >= 1 and specific scaling dimension constraints.

Findings

Derived a lower bound for boundary entropy g in 1+1d quantum critical systems.

Established restrictions on possible boundary conditions based on conformal data.

Provides a theoretical framework for understanding boundary effects in critical quantum systems.

Abstract

A lower bound is derived for the boundary entropy s = ln g of a 1+1d quantum critical system with boundary, under the conditions that the bulk conformal central charge c is >=1 and the most relevant bulk scaling dimension is >(c-1)/12. This is the first general restriction on the possible values of g for bulk critical systems with c >= 1.