Non-Hermitian Renormalization Group from a Few-Body Perspective

• URL: http://arxiv.org/abs/2602.08705v1
• Date: Mon, 09 Feb 2026 14:19:15 GMT
• Title: Non-Hermitian Renormalization Group from a Few-Body Perspective
• Authors: Hiroyuki Tajima, Masaya Nakagawa, Haozhao Liang, Masahito Ueda,
• Abstract summary: We establish a microscopic foundation of the non-Hermitian RG method from a few-body perspective.<n>We show that the invariance of the scattering amplitude under RG transformations enables us to rigorously derive the non-Hermitian RG equation.<n>We discuss a detailed structure of such RG flows in a non-relativistic two-body system with inelastic two-body loss, and show its relation to a non-Hermitian quantum scale anomaly.
• Score: 4.024850952459758
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: Non-Hermiticity plays a fundamental role in open quantum systems and describes a wide variety of effects of interactions with environments, including quantum measurement. However, understanding its consequences in strongly interacting systems is still elusive due to the interplay between non-perturbative strong correlations and non-Hermiticity. While the Wilsonian renormalization group (RG) method has been applied to tackle this problem, its foundation, based on the existence of the partition function, is ill-defined. In this paper, we establish a microscopic foundation of the non-Hermitian RG method from a few-body perspective. We show that the invariance of the scattering amplitude under RG transformations enables us to rigorously derive the non-Hermitian RG equation, giving a physically transparent interpretation of RG flows. We discuss a detailed structure of such RG flows in a non-relativistic two-body system with inelastic two-body loss, and show its relation to a non-Hermitian quantum scale anomaly. Our analysis suggests that non-Hermitian complex potentials often used in high-energy physics can be interpreted as being caused by quantum measurement, where the detection of elastically scattered particles updates the observer's knowledge, resulting in a nonunitary state change of the system. We apply our formalism to nuclear physics, find the emergence of a critical semicircle, and show that several nuclei are located near the critical semicircle in the coherent neutron-nucleus scattering. We also propose that the localized dineutron in two-neutron halo nuclei can be interpreted as the quantum measurement effect on the imaginary potential associated with absorption into the core nucleus. Our result bridges different contexts of non-Hermitian systems in high-energy and atomic, molecular, and optical physics, opening an interdisciplinary playground of non-Hermitian few-body physics.

Related papers

• Steady-state skin effect in bosonic topological edge states under parametric driving [0.0]
  We focus on the quantum nature inherent in bosonic Bogoliubov-de Gennes (BdG) systems.<n>We propose a steady-state skin effect in quantum condensed matter utilizing such BdG non-Hermiticity.
  arXiv  Detail & Related papers  (2026-02-02T04:38:38Z)
• Unveiling non-Hermitian band structures with non-Bloch supercells [23.45255537572689]
  Non-Hermitian systems exhibit complex band structures where both energy and momentum have imaginary parts.<n>We introduce a non-Bloch supercell framework designed to overcome this challenge by decoupling Bloch phase control from the imaginary part of momentum.
  arXiv  Detail & Related papers  (2025-10-23T03:18:23Z)
• Observation of non-Hermitian topology in cold Rydberg quantum gases [42.41909362660157]
  We experimentally demonstrate non-Hermitian spectra topology in a dissipative Rydberg atomic gas.<n>By increasing the interaction strength, the system evolves from Hermitian to non-Hermitian regime.<n>This work establishes cold Rydberg gases as a versatile platform for exploring the rich interplay between non-Hermitian topology, strong interactions, and dissipative quantum dynamics.
  arXiv  Detail & Related papers  (2025-09-30T13:44:43Z)
• Theory of the correlated quantum Zeno effect in a monitored qubit dimer [41.94295877935867]
  We show how the competition between two measurement processes give rise to two distinct Quantum Zeno (QZ) regimes.<n>We develop a theory based on a Gutzwiller ansatz for the wavefunction that is able to capture the structure of the Hilbert phase diagram.<n>We show how the two QZ regimes are intimately connected to the topology of the flow of the underlying non-Hermitian Hamiltonian governing the no-click evolution.
  arXiv  Detail & Related papers  (2025-03-28T19:44:48Z)
• Entanglement Hamiltonian and effective temperature of non-Hermitian quantum spin ladders [0.0]
  We analytically investigate the entanglement Hamiltonian and entanglement energy spectrum of a non-Hermitian spin ladder. Our findings provide new insights into quantum entanglement in non-Hermitian systems.
  arXiv  Detail & Related papers  (2024-09-25T16:20:24Z)
• Nontrivial worldline winding in non-Hermitian quantum systems [3.8601741392210434]
  We investigate non-Hermitian physics in interacting quantum systems, e.g., various non-Hermitian quantum spin chains. We study the direct physical implications of such nontrivial worldline winding, which bring additional, potentially quasi-long-range contributions to the entanglement entropy.
  arXiv  Detail & Related papers  (2023-07-03T18:00:02Z)
• Discord and Decoherence [0.0]
  We investigate how quantum discord is modified by a quantum-to-classical transition. We find that the evolution of quantum discord in presence of an environment is a competition between the growth of the squeezing amplitude and the decrease of the state purity.
  arXiv  Detail & Related papers  (2021-12-09T17:01:54Z)
• Bridging the gap between topological non-Hermitian physics and open quantum systems [62.997667081978825]
  We show how to detect a transition between different topological phases by measuring the response to local perturbations. Our formalism is exemplified in a 1D Hatano-Nelson model, highlighting the difference between the bosonic and fermionic cases.
  arXiv  Detail & Related papers  (2021-09-22T18:00:17Z)
• Breakdown of quantum-classical correspondence and dynamical generation of entanglement [6.167267225728292]
  We study the generation of quantum entanglement induced by an ideal Fermi gas confined in a chaotic cavity. We find that the breakdown of the quantum-classical correspondence of particle motion, via dramatically changing the spatial structure of many-body wavefunction, leads to profound changes of the entanglement structure.
  arXiv  Detail & Related papers  (2021-04-14T03:09:24Z)
• Non-equilibrium stationary states of quantum non-Hermitian lattice models [68.8204255655161]
  We show how generic non-Hermitian tight-binding lattice models can be realized in an unconditional, quantum-mechanically consistent manner. We focus on the quantum steady states of such models for both fermionic and bosonic systems.
  arXiv  Detail & Related papers  (2021-03-02T18:56:44Z)
• Einselection from incompatible decoherence channels [62.997667081978825]
  We analyze an open quantum dynamics inspired by CQED experiments with two non-commuting Lindblad operators. We show that Fock states remain the most robust states to decoherence up to a critical coupling.
  arXiv  Detail & Related papers  (2020-01-29T14:15:19Z)

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.