Optimal continuity bound for the von Neumann entropy under energy constraints
- URL: http://arxiv.org/abs/2410.02686v1
- Date: Thu, 3 Oct 2024 17:14:24 GMT
- Title: Optimal continuity bound for the von Neumann entropy under energy constraints
- Authors: S. Becker, N. Datta, M. G. Jabbour, M. E. Shirokov,
- Abstract summary: We construct a globally optimal continuity bound for the von Neumann entropy under energy constraints imposed by arbitrary Hamiltonians.
It completely solves the problem of finding an optimal continuity bound for the von Neumann entropy in this setting.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Using techniques proposed in [Sason, IEEE Trans. Inf. Th. 59, 7118 (2013)] and [Becker, Datta and Jabbour, IEEE Trans. Inf. Th. 69, 4128 (2023)], and building on results from the latter, we construct a globally optimal continuity bound for the von Neumann entropy under energy constraints imposed by arbitrary Hamiltonians, satisfying the Gibbs hypothesis. In particular, this provides a precise expression for the modulus of continuity of the von Neumann entropy over the set of states with bounded energy for infinite-dimensional quantum systems. Thus, it completely solves the problem of finding an optimal continuity bound for the von Neumann entropy in this setting, which was previously known only for pairs of states which were sufficiently close to each other. This continuity bound follows from a globally optimal semicontinuity bound for the von Neumann entropy under general energy constraints, which is our main technical result.
Related papers
- Revisiting the operator extension of strong subadditivity [44.99833362998488]
We give a new proof of the operator extension of the strong subadditivity of von Neumann entropy $rho_AB otimes sigma_C-1 leq rho_A otimes sigma_BC-1$ by identifying the mathematical structure behind it as Connes' theory of spatial derivatives.
arXiv Detail & Related papers (2025-07-30T14:18:43Z) - Semicontinuity bounds for the von Neumann entropy and partial majorization [0.0]
We consider families of tight upper bounds on the difference $S(rho)-S(sigma)$ with the rank/energy constraint imposed on the state $rho$.<n>The upper bounds within these families depend on the parameter $m$ of partial majorization.
arXiv Detail & Related papers (2025-04-10T19:55:06Z) - Continuity bounds for quantum entropies arising from a fundamental entropic inequality [9.23607423080658]
We establish a tight upper bound for the difference in von Neumann entropies between two quantum states, $rho_1$ and $rho$.
This yields a novel entropic inequality that implies the well-known Audenaert-Fannes (AF) inequality.
arXiv Detail & Related papers (2024-08-27T15:59:38Z) - The Limits of Pure Exploration in POMDPs: When the Observation Entropy is Enough [40.82741665804367]
We study a simple approach of maximizing the entropy over observations in place true latent states.
We show how knowledge of the latter can be exploited to compute a regularization of the observation entropy to improve principled performance.
arXiv Detail & Related papers (2024-06-18T17:00:13Z) - Learning with Norm Constrained, Over-parameterized, Two-layer Neural Networks [54.177130905659155]
Recent studies show that a reproducing kernel Hilbert space (RKHS) is not a suitable space to model functions by neural networks.
In this paper, we study a suitable function space for over- parameterized two-layer neural networks with bounded norms.
arXiv Detail & Related papers (2024-04-29T15:04:07Z) - Coherence generation with Hamiltonians [44.99833362998488]
We explore methods to generate quantum coherence through unitary evolutions.
This quantity is defined as the maximum derivative of coherence that can be achieved by a Hamiltonian.
We identify the quantum states that lead to the largest coherence derivative induced by the Hamiltonian.
arXiv Detail & Related papers (2024-02-27T15:06:40Z) - General Continuity Bounds for Quantum Relative Entropies [0.24999074238880484]
We introduce a method to prove continuity bounds for quantities derived from different quantum relative entropies.
For the Umegaki relative entropy, we mostly recover known almost optimal bounds, whereas, for the Belavkin-Staszewski relative entropy, our bounds are new.
arXiv Detail & Related papers (2023-05-17T11:52:15Z) - Entropy Constraints for Ground Energy Optimization [10.2138250640885]
We study the use of von Neumann entropy constraints for obtaining lower bounds on the ground energy of quantum many-body systems.
Known methods for obtaining certificates on the ground energy typically use consistency of local observables and are expressed as semidefinite programming relaxations.
arXiv Detail & Related papers (2023-05-11T14:51:21Z) - Asymptotic Equipartition Theorems in von Neumann algebras [24.1712628013996]
We show that the smooth max entropy of i.i.d. states on a von Neumann algebra has an rate given by the quantum relative entropy.
Our AEP not only applies to states, but also to quantum channels with appropriate restrictions.
arXiv Detail & Related papers (2022-12-30T13:42:35Z) - Boosting the Confidence of Generalization for $L_2$-Stable Randomized
Learning Algorithms [41.082982732100696]
We show that a properly designed subbagging process leads to near-tight exponential generalization bounds over both data and algorithm.
We further derive generic results to improve high-probability generalization bounds for convex or non-tight problems with natural decaying learning rates.
arXiv Detail & Related papers (2022-06-08T12:14:01Z) - A Quantum Optimal Control Problem with State Constrained Preserving
Coherence [68.8204255655161]
We consider a three-level $Lambda$-type atom subjected to Markovian decoherence characterized by non-unital decoherence channels.
We formulate the quantum optimal control problem with state constraints where the decoherence level remains within a pre-defined bound.
arXiv Detail & Related papers (2022-03-24T21:31:34Z) - 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) - Convergence Error Analysis of Reflected Gradient Langevin Dynamics for Globally Optimizing Non-Convex Constrained Problems [38.544941658428534]
Gradient Langevin dynamics and its variants have attracted increasing attention to their convergence towards the global optimal solution, initially in the global equation.
In this paper we present a new type of convex constrained non-constrained boundary problem.
arXiv Detail & Related papers (2022-03-19T02:08:24Z) - A relation among tangle, 3-tangle, and von Neumann entropy of
entanglement for three qubits [0.0]
We derive a formula of the tangle for pure states of three qubits, and present three explicit local unitary (LU) invariants.
Our result goes beyond the classical work of tangle, 3-tangle and von Neumann entropy of entanglement.
We obtain all the states of three qubits of which tangles, concurrence, 3-tangle and von Neumann entropy don't vanish.
arXiv Detail & Related papers (2022-03-17T20:55:51Z) - High Fidelity Quantum State Transfer by Pontryagin Maximum Principle [68.8204255655161]
We address the problem of maximizing the fidelity in a quantum state transformation process satisfying the Liouville-von Neumann equation.
By introducing fidelity as the performance index, we aim at maximizing the similarity of the final state density operator with the one of the desired target state.
arXiv Detail & Related papers (2022-03-07T13:27:26Z) - Tight Exponential Analysis for Smoothing the Max-Relative Entropy and
for Quantum Privacy Amplification [56.61325554836984]
The max-relative entropy together with its smoothed version is a basic tool in quantum information theory.
We derive the exact exponent for the decay of the small modification of the quantum state in smoothing the max-relative entropy based on purified distance.
arXiv Detail & Related papers (2021-11-01T16:35:41Z) - Kurtosis of von Neumann entanglement entropy [2.88199186901941]
We study the statistical behavior of entanglement in quantum bipartite systems under the Hilbert-Schmidt ensemble.
The main contribution of the present work is the exact formula of the corresponding fourth cumulant that controls the tail behavior of the distribution.
arXiv Detail & Related papers (2021-07-21T22:20:10Z) - From Classical to Quantum: Uniform Continuity Bounds on Entropies in Infinite Dimensions [12.958449178903727]
We prove uniform continuity bounds for entropies of classical random variables on an infinite state space and of quantum states of infinite-dimensional systems.
The proof relies on a new mean-constrained Fano-type inequality and the notion of maximal coupling of random variables.
arXiv Detail & Related papers (2021-04-05T17:18:42Z) - Debiased Sinkhorn barycenters [110.79706180350507]
Entropy regularization in optimal transport (OT) has been the driver of many recent interests for Wasserstein metrics and barycenters in machine learning.
We show how this bias is tightly linked to the reference measure that defines the entropy regularizer.
We propose debiased Wasserstein barycenters that preserve the best of both worlds: fast Sinkhorn-like iterations without entropy smoothing.
arXiv Detail & Related papers (2020-06-03T23:06:02Z) - Quantum Geometric Confinement and Dynamical Transmission in Grushin
Cylinder [68.8204255655161]
We classify the self-adjoint realisations of the Laplace-Beltrami operator minimally defined on an infinite cylinder.
We retrieve those distinguished extensions previously identified in the recent literature, namely the most confining and the most transmitting.
arXiv Detail & Related papers (2020-03-16T11:37:23Z) - Witnessing Negative Conditional Entropy [0.0]
We prove the existence of a Hermitian operator for the detection of states having negative conditional entropy for bipartite systems.
We find that for a particular witness, the estimated tight upper bound matches the value of conditional entropy for Werner states.
arXiv Detail & Related papers (2020-01-30T10:08:10Z)
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.