On the Clustering of Conditional Mutual Information via Dissipative Dynamics
- URL: http://arxiv.org/abs/2504.02235v1
- Date: Thu, 03 Apr 2025 03:06:55 GMT
- Title: On the Clustering of Conditional Mutual Information via Dissipative Dynamics
- Authors: Kohtaro Kato, Tomotaka Kuwahara,
- Abstract summary: Conditional mutual information (CMI) has attracted significant attention as a key quantity for characterizing quantum correlations in many-body systems.<n>It is conjectured that CMI decays rapidly in finite-temperature Gibbs states.<n>Previous work addressed this problem in the high-temperature regime using cluster expansion techniques.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Conditional mutual information (CMI) has recently attracted significant attention as a key quantity for characterizing quantum correlations in many-body systems. While it is conjectured that CMI decays rapidly in finite-temperature Gibbs states, a complete and general proof remains elusive. Previous work addressed this problem in the high-temperature regime using cluster expansion techniques [T. Kuwahara, K. Kato, F.G.S.L. Brand\~ao, Phys. Rev. Lett. 124, 220601 (2020)]; however, flaws in the proof have been pointed out, and the method does not provide a uniformly convergent expansion at arbitrarily high temperatures. In this work, we demonstrate that the cluster expansion approach indeed fails to converge absolutely, even at any high-temperatures. To overcome this limitation, we propose a new approach to proving the spatial decay of CMI. Our method leverages the connection between CMI and quantum recovery maps, specifically utilizing the Fawzi-Renner theorem. We show that such recovery maps can be realized through dissipative dynamics, and by analyzing the locality properties of these dynamics, we establish the exponential decay of CMI in high-temperature regimes. As a technical contribution, we also present a new result on the perturbative stability of quasi-local Liouvillian dynamics. Our results indicate that, contrary to common intuition, high-temperature Gibbs states can exhibit nontrivial mathematical structure, particularly when multipartite correlations such as CMI are considered.
Related papers
- Quantum Gibbs states are locally Markovian [1.9643748953805944]
We show that for any Hamiltonian with a bounded interaction degree, the quantum Gibbs state is locally Markov at arbitrary temperature.
We introduce a regularization scheme for imaginary-time-evolved operators at arbitrarily low temperatures.
arXiv Detail & Related papers (2025-04-03T01:54:42Z) - Conditional Mutual Information and Information-Theoretic Phases of Decohered Gibbs States [5.062448779099901]
Adding local dissipation to a Markov network turns it into a emphhidden Markov network.<n>We show that low-temperature hidden Markov networks can sustain long-range CMI.
arXiv Detail & Related papers (2025-02-18T19:00:02Z) - Crosscap Quenches and Entanglement Evolution [0.0]
We propose a novel quench protocol, termed the "crosscap quench"<n>We analyze conformal field theories (CFTs) and derive universal features in the time evolution of the entanglement entropy.<n>We validate these findings through numerical simulations in both nonintegrable and integrable quantum spin systems.
arXiv Detail & Related papers (2024-12-24T18:59:58Z) - Gapless Floquet topology [40.2428948628001]
We study the existence of topological edge zero- and pi-modes despite the lack of bulk gaps in the quasienergy spectrum.
We numerically study the effect of interactions, which give a finite lifetime to the edge modes in the thermodynamic limit with the decay rate consistent with Fermi's Golden Rule.
arXiv Detail & Related papers (2024-11-04T19:05:28Z) - Clustering of conditional mutual information and quantum Markov structure at arbitrary temperatures [0.0]
Recent investigations have unveiled exotic quantum phases that elude characterization by simple bipartite correlation functions.
In these phases, long-range entanglement arising from tripartite correlations plays a central role.
Our findings unveil that, even at low temperatures, a broad class of tripartite entanglement cannot manifest in the long-range regime.
arXiv Detail & Related papers (2024-07-08T11:30:12Z) - Many-Body Localization in the Age of Classical Computing [0.0]
This review focuses on recent numerical investigations aiming to clarify the status of the MBL phase.<n>The drifts are related to tendencies towards thermalization and non-vanishing transport observed in the dynamics of many-body systems.<n>Questions about thermalization and its failure in disordered many-body systems remain captivating area open for further explorations.
arXiv Detail & Related papers (2024-03-11T19:00:06Z) - Neural-network quantum states for ultra-cold Fermi gases [49.725105678823915]
This work introduces a novel Pfaffian-Jastrow neural-network quantum state that includes backflow transformation based on message-passing architecture.
We observe the emergence of strong pairing correlations through the opposite-spin pair distribution functions.
Our findings suggest that neural-network quantum states provide a promising strategy for studying ultra-cold Fermi gases.
arXiv Detail & Related papers (2023-05-15T17:46:09Z) - Genuine Multipartite Correlations in a Boundary Time Crystal [56.967919268256786]
We study genuine multipartite correlations (GMC's) in a boundary time crystal (BTC)
We analyze both (i) the structure (orders) of GMC's among the subsystems, as well as (ii) their build-up dynamics for an initially uncorrelated state.
arXiv Detail & Related papers (2021-12-21T20:25:02Z) - 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) - Out-of-time-order correlations and the fine structure of eigenstate
thermalisation [58.720142291102135]
Out-of-time-orderors (OTOCs) have become established as a tool to characterise quantum information dynamics and thermalisation.
We show explicitly that the OTOC is indeed a precise tool to explore the fine details of the Eigenstate Thermalisation Hypothesis (ETH)
We provide an estimation of the finite-size scaling of $omega_textrmGOE$ for the general class of observables composed of sums of local operators in the infinite-temperature regime.
arXiv Detail & Related papers (2021-03-01T17:51:46Z) - Probing eigenstate thermalization in quantum simulators via
fluctuation-dissipation relations [77.34726150561087]
The eigenstate thermalization hypothesis (ETH) offers a universal mechanism for the approach to equilibrium of closed quantum many-body systems.
Here, we propose a theory-independent route to probe the full ETH in quantum simulators by observing the emergence of fluctuation-dissipation relations.
Our work presents a theory-independent way to characterize thermalization in quantum simulators and paves the way to quantum simulate condensed matter pump-probe experiments.
arXiv Detail & Related papers (2020-07-20T18:00:02Z)
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.