# Anomaly Manifestation of Lieb-Schultz-Mattis Theorem and Topological Phases

## TL;DR

This paper explores the connection between the Lieb-Schultz-Mattis theorem and topological phases, revealing how quantum anomalies differentiate their roles in enforcing gapless states and symmetric insulators.

## Contribution

It demonstrates that identical low-energy theories can have different anomaly roles, extending the LSM theorem to multi-charge systems and analyzing anomaly stability in topological phases.

## Key findings

- Chiral anomaly corresponds to the LSM theorem.
- Identification of a new anomaly intrinsic to SPT states.
- Extension of LSM theorem to multi-charge, multi-species systems.

## Abstract

The Lieb-Schultz-Mattis (LSM) theorem dictates that emergent low-energy states from a lattice model cannot be a trivial symmetric insulator if the filling per unit cell is not integral and if the lattice translation symmetry and particle number conservation are strictly imposed. In this paper, we compare the one-dimensional gapless states enforced by the LSM theorem and the boundaries of one-higher dimensional strong symmetry-protected topological (SPT) phases from the perspective of quantum anomalies. We first note that, they can be both described by the same low-energy effective field theory with the same effective symmetry realizations on low-energy modes, wherein non-on-site lattice translation symmetry is encoded as if it is a local symmetry. In spite of the identical form of the low-energy effective field theories, we show that the quantum anomalies of the theories play different roles in the two systems. In particular, We find that the chiral anomaly is equivalent to the LSM theorem, whereas there is another anomaly, which is not related to the LSM theorem but is intrinsic to the SPT states. As an application, we extend the conventional LSM theorem to multiple-charge multiple-species problems and construct several exotic symmetric insulators. We also find that the (3+1)d chiral anomaly provides only the perturbative stability of the gapless-ness local in the parameter space.