Subsystem eigenstate thermalization hypothesis

TLDR

Quantum statistical physics in isolated many‑body systems is commonly described by Canonical Typicality or the Eigenstate Thermalization Hypothesis, which differ yet overlap in validity, phenomenology, and predicted outcomes. The paper investigates the relationship between Canonical Typicality and the Eigenstate Thermalization Hypothesis. It proposes a formulation of ETH using the reduced density matrix. Numerical evidence strongly supports the proposed reduced‑density‑matrix formulation of ETH. The article has been withdrawn and superseded by arXiv:1611.08764.

Abstract

Currently there are two main approaches to describe how quantum statistical physics emerges from an isolated quantum many-body system in a pure state: Canonical Typicality (CT) and Eigenstate Thermalization Hypothesis (ETH). These two approaches has different but overlapping areas of validity, phenomenology and set of physical outcomes. In this paper we discuss the relation between CT and ETH and propose a formulation of ETH in terms of the reduced density matrix. We provide strong numerical evidences for the proposal. This article has been withdrawn as it is superseded by arXiv:1611.08764