Quantum matter is weakly entangled at low energies

• URL: http://arxiv.org/abs/2604.14143v1
• Date: Wed, 15 Apr 2026 17:59:04 GMT
• Title: Quantum matter is weakly entangled at low energies
• Abstract summary: We study entanglement entropies of subsystems that make up approximately half of the full system.<n>Our results relate physical thermodynamic properties to the structure of many-body Hilbert space at low energies.
• Score: 0.006617690382056421
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We construct upper bounds on entanglement entropies of many-body quantum states that have fixed energy expectation values with respect to geometrically local Hamiltonians. Our focus is on entanglement entropies of subsystems that make up approximately half of the full system. The upper bound on the von Neumann entanglement entropy is half the sum of the thermal entropies of two fictitious systems at the same temperature as one another, with an additional area-law contribution in some systems. The effective temperature is chosen such that the sum of the thermal energies of the two fictitious systems matches the constraint on the energy of the state in the original problem; at subextensive energies, this temperature decreases with increasing system size. Our upper bounds on Rényi entanglement entropies take an analogous form. As a first application we show that ground-state Schmidt ranks in frustration-free (FF) systems are upper bounded by the ground-state degeneracies of Hamiltonians acting on subsystems. Ground-state von Neumann and Rényi entanglement entropies therefore follow an area law when the zero-temperature thermal entropies of subsystems scale with surface areas, rather than with subsystem volumes. This result holds independently of the spectral gap. For physical models of quantum matter, which have well-defined specific heat capacities (and are not necessarily FF), our bounds provide a way to convert this thermodynamic data into constraints on pure-state entanglement at both subextensive and extensive energies. We also show that our upper bounds on half-system entanglement entropies are optimal, up to subleading corrections, in wide varieties of systems. Our results relate physical thermodynamic properties to the structure of many-body Hilbert space at low energies.

Related papers

• The Large-Scale Structure of Entanglement in Quantum Many-body Systems [44.99833362998488]
  We show that the thermodynamic limit of a many-body system can reveal entanglement properties that are hard to detect in finite-size systems.<n>In particular, we show that every gapped phase of matter, even the trivial one, in $Dgeq 2$ dimensions contains models with the strongest possible bipartite large-scale entanglement.
  arXiv  Detail & Related papers  (2025-03-05T19:01:05Z)
• Scrambling Enabled Entropy Accumulation in Open Quantum Systems [12.410361153759757]
  In closed quantum many-body systems, initially localized information spreads throughout the system and becomes highly complex.<n>Recent studies have shown that dissipation in open systems can hinder information scrambling, driving the system into a dissipative phase.<n>We unveil a novel phenomenon in open quantum systems, termed entropy accumulation, which occurs exclusively within the scrambling phase.
  arXiv  Detail & Related papers  (2025-02-11T11:24:09Z)
• Thermodynamics of the Page curve in Markovian open quantum systems [0.0]
  We study the entropy dynamics for Lindbladian evolution in weak contact with Markovian reservoirs.<n>We give an analytic expression of the entanglement dynamics for a decaying excitation in a two-level system.
  arXiv  Detail & Related papers  (2025-01-15T19:01:04Z)
• The Eigenstate Thermalization Hypothesis in a Quantum Point Contact Geometry [0.0]
  It is known that the long-range quantum entanglement exhibited in free fermion systems is sufficient to "thermalize" a small subsystem.<n>We show that entanglement entropy of a subsystem connected by a small number of quantum point contacts is sub-extensive, scaling as the linear size of the subsystem.
  arXiv  Detail & Related papers  (2025-01-06T15:19:17Z)
• Quantum Entanglement and the Thermal Hadron [0.0]
  This paper tests how effectively the bound states of strongly interacting gauge theories are amenable to an emergent description as a thermal ensemble. This description can be derived from a conjectured minimum free energy principle, with the entanglement entropy of two-parton subsystems playing the role of thermodynamic entropy.
  arXiv  Detail & Related papers  (2022-11-25T19:00:03Z)
• Nonperturbative renormalization of quantum thermodynamics from weak to strong couplings [2.542198147027801]
  By solving the exact master equation of open quantum systems, we formulate the quantum thermodynamics from weak to strong couplings. We find that the exact solution of the reduced density matrix of these systems approaches a Gibbs-type state in the steady-state limit for both the weak and strong system-reservoir coupling strengths.
  arXiv  Detail & Related papers  (2022-05-17T06:25:03Z)
• Maximum entropy quantum state distributions [58.720142291102135]
  We go beyond traditional thermodynamics and condition on the full distribution of the conserved quantities. The result are quantum state distributions whose deviations from thermal states' get more pronounced in the limit of wide input distributions.
  arXiv  Detail & Related papers  (2022-03-23T17:42:34Z)
• Thermoelectric properties of topological chains coupled to a quantum dot [40.19796930944118]
  Topological one-dimensional superconductors can sustain in their extremities zero energy modes that are protected by different kinds of symmetries. We consider the simplest kind of topological insulators, namely chains of atoms with hybridized $sp$ orbitals. We show that the electrical conductance and the Wiedemann-Franz ratio of the device at the topological transition have universal values at very low temperatures.
  arXiv  Detail & Related papers  (2021-12-20T22:52:00Z)
• Fast Thermalization from the Eigenstate Thermalization Hypothesis [69.68937033275746]
  Eigenstate Thermalization Hypothesis (ETH) has played a major role in understanding thermodynamic phenomena in closed quantum systems. This paper establishes a rigorous link between ETH and fast thermalization to the global Gibbs state. Our results explain finite-time thermalization in chaotic open quantum systems.
  arXiv  Detail & Related papers  (2021-12-14T18:48:31Z)
• Open-system approach to nonequilibrium quantum thermodynamics at arbitrary coupling [77.34726150561087]
  We develop a general theory describing the thermodynamical behavior of open quantum systems coupled to thermal baths. Our approach is based on the exact time-local quantum master equation for the reduced open system states.
  arXiv  Detail & Related papers  (2021-09-24T11:19:22Z)
• Taking the temperature of a pure quantum state [55.41644538483948]
  Temperature is a deceptively simple concept that still raises deep questions at the forefront of quantum physics research. We propose a scheme to measure the temperature of such pure states through quantum interference.
  arXiv  Detail & Related papers  (2021-03-30T18:18:37Z)
• One-to-one correspondence between entanglement mechanics and black hole thermodynamics [0.0]
  We establish a one-to-one mapping between entanglement entropy, energy, and temperature. We show this universally for 4-D spherically symmetrically flat and non-flat space-times with single and multiple horizons.
  arXiv  Detail & Related papers  (2020-10-07T13:57:57Z)
• Temperature of a finite-dimensional quantum system [68.8204255655161]
  A general expression for the temperature of a finite-dimensional quantum system is deduced from thermodynamic arguments. Explicit formulas for the temperature of two and three-dimensional quantum systems are presented.
  arXiv  Detail & Related papers  (2020-05-01T07:47:50Z)
• Out-of-equilibrium quantum thermodynamics in the Bloch sphere: temperature and internal entropy production [68.8204255655161]
  An explicit expression for the temperature of an open two-level quantum system is obtained. This temperature coincides with the environment temperature if the system reaches thermal equilibrium with a heat reservoir. We show that within this theoretical framework the total entropy production can be partitioned into two contributions.
  arXiv  Detail & Related papers  (2020-04-09T23:06:43Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.