10 papers
A local description of strong symmetries and strong-to-weak symmetry breaking in quantum many-body systems
Ruizhi Liu, Jinmin Yi, Dominic V. Else
In mixed states of quantum systems, symmetries come in two types: strong and weak. Furthermore, it has been argued that in quantum many-body systems, strong symmetries can be "spon…
Anomalies in quantum spin systems and Nielsen-Ninomiya type Theorems
Ruizhi Liu
We provide an algebraic perspective on Nielsen--Ninomiya-type no-go theorems arising from group cohomological anomalies, revisiting in particular the version proved by Kapustin and…
When does a lattice higher-form symmetry flow to a topological higher-form symmetry at low energies?
Ruizhi Liu, Pok Man Tam, Ho Tat Lam +1
We study the lattice version of higher-form symmetries on tensor-product Hilbert spaces. Interestingly, at low energies, these symmetries may not flow to the topological higher-for…
Entanglement area law and Lieb-Schultz-Mattis theorem in long-range interacting systems, and symmetry-enforced long-range entanglement
Ruizhi Liu, Jinmin Yi, Shiyu Zhou +1
We establish multiple interrelated, fundamental results in quantum many-body systems that can have long-range interactions. For a sufficiently long quantum spin chain, we first sho…
Twisted locality-preserving automorphisms, anomaly index, and generalized Lieb-Schultz-Mattis theorems with anti-unitary symmetries
Ruizhi Liu, Jinmin Yi, Liujun Zou
Symmetries and their anomalies are powerful tools to understand quantum matter. In this work, for quantum spin chains, we define twisted locality-preserving automorphisms and their…
Lovász Meets Lieb-Schultz-Mattis: Complexity in Approximate Quantum Error Correction
Jinmin Yi, Ruizhi Liu, Zhi Li
Approximate quantum error correction (AQEC) provides a versatile framework for both quantum information processing and probing many-body entanglement. We reveal a fundamental tensi…