Topological Entropy and Renormalization Group flow in 3-dimensional spherical spaces

TL;DR

This paper investigates how the topological entropy in 3D spherical spaces behaves under renormalization group flow, revealing a monotonic decrease that suggests a 3D analog of the c-theorem and connections to entanglement entropy.

Contribution

It demonstrates the monotonic behavior of holonomy entropy in 3D spherical spaces under RG flow and proposes a generalization of the c-theorem in three dimensions.

Findings

Holonomy entropy decreases monotonically along RG flow.

At fixed points, holonomy entropy matches topological entropy.

Relation established between holonomy entropy and entanglement entropy on disks.

Abstract

We analyze the renormalization group (RG) flow of the temperature independent term of the entropy in the high temperature limit \beta/a<<1 of a massive field theory in 3-dimensional spherical spaces M_3 with constant curvature 6/a^2. For masses lower than 2\pi/\beta, this term can be identified with the free energy of the same theory on M_3 considered as a 3-dimensional Euclidean space-time. The non-extensive part of this free energy, S_hol, is generated by the holonomy of the spatial metric connection. We show that for homogeneous spherical spaces the holonomy entropy S_hol decreases monotonically when the RG scale flows to the infrared. At the conformal fixed points the values of the holonomy entropy do coincide with the genuine topological entropies recently introduced. The monotonic behavior of the RG flow leads to an inequality between the topological entropies of the conformal field theories connected by such flow, i.e. S_top^UV > S_top^IR. From a 3-dimensional viewpoint the same term arises in the 3-dimensional Euclidean effective action and has the same monotonic behavior under the RG group flow. We conjecture that such monotonic behavior is generic, which would give rise to a 3-dimensional generalization of the c-theorem, along the lines of the 2-dimensional c-theorem and the 4-dimensional a-theorem. The conjecture is related to recent formulations of the F-theorem. In particular, the holonomy entropy on lens spaces is directly related to the topological R\'enyi entanglement entropy on disks of 2-dimensional flat spaces.