Violation of steering inequality for generalized equiangular measurements
- URL: http://arxiv.org/abs/2504.08497v1
- Date: Fri, 11 Apr 2025 12:54:00 GMT
- Title: Violation of steering inequality for generalized equiangular measurements
- Abstract summary: We study bipartite quantum steering using a general class of measurement operators known as the generalized equiangular measurement (GEAM)<n>Our approach allows for the construction of steering inequalities that are applicable not only to informationally complete measurements but also to incomplete or lossy scenarios.
- Score: 0.6906005491572401
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: In this article, we study bipartite quantum steering using a general class of measurement operators known as the generalized equiangular measurement (GEAM). Our approach allows for the construction of steering inequalities that are applicable not only to informationally complete measurements but also to incomplete or lossy scenarios, where the resulting quantum assemblages may be subnormalized. We develop a method to analytically bound the value of steering functionals under local hidden state (LHS) models by employing a generalized inequality for the eigenvalues of positive semidefinite operators, extending classical results such as the Samuelson inequality. This yields universal upper bounds on the LHS value in terms of the parameters defining the frame. Furthermore, we analyze the asymptotic behavior of these bounds in high-dimensional Hilbert spaces and demonstrate the possibility of unbounded quantum violations of steering inequalities. Our formalism encompasses previously known results for mutually unbiased bases (MUBs) and mutually unbiased measurements (MUMs) as special cases, showing that these are particular instances within a unified and more general framework.
Related papers
- Characterising extremal decoherence by quantum measurement incompatibility [0.0]
We show that decoherence can turn incompatible measurements into jointly measurable ones.<n>The corresponding loss of incompatibility can be captured by the channel's emphcompatibility region.
arXiv Detail & Related papers (2026-07-23T10:56:33Z) - Causal-Order Identification of Memoryless Sequential Quantum Processes from Restricted Projective Data [45.85698554568285]
We find necessary and sufficient conditions for deciding when an observed distribution is compatible with a memoryless sequential quantum process in a fixed direction.<n>We then specialize to the two-qubit Pauli setting, where the problem remains non-tomographic but becomes explicitly tractable.
arXiv Detail & Related papers (2026-05-06T07:16:29Z) - Typical entanglement in anyon chains: Page curves beyond Lie group symmetries [41.99844472131922]
We study bipartite entanglement statistics in one-dimensional anyon chains constrained by fusion rules of unitary pre-modular categories.<n>Surprisingly, despite the constrained Hilbert space structure, the large $L$ expansion has no universal $O(sqrtL)$ or $O(1)$ symmetry-type corrections.<n> Numerical simulations of the integrable and quantum-chaotic golden chain Hamiltonian show that chaotic mid-spectrum eigenstates match the Haar-random predictions.
arXiv Detail & Related papers (2026-03-26T18:00:03Z) - Factorisation conditions and causality for local measurements in QFT [0.0]
Quantum operations that are perfectly admissible in non-relativistic quantum theory can enable signalling when naively imported into quantum field theory (QFT)<n>Prominent examples of such "impossible measurements", in the sense of Sorkin, include certain unitary kicks and projective measurements.<n>We show that the accuracy with which local field observables can be measured is fundamentally limited by the retarded propagator of the field.
arXiv Detail & Related papers (2025-11-26T18:15:21Z) - Certifying Majorana Fermions with Elegant-Like Bell Inequalities and a New Self-Testing Equivalence [0.11199585259018459]
We introduce a general construction of Bell inequalities for which this bound can be computed exactly.<n>Our framework generalizes both the Clauser-Horne-Shimony-Holt and Gisin's elegant inequalities.<n>Under suitable assumptions, our inequalities also enable the device-independent certification of Majorana fermions.
arXiv Detail & Related papers (2025-11-21T20:27:34Z) - Most incompatible measurements and sum-of-squares optimisation [0.0]
Measurement incompatibility, or joint measurability, is a cornerstone of quantum theory and a useful resource.<n>We show analytical universal parent measurements giving access to bounds that beat the state of the art.<n>Results find direct application for demonstrating genuine high-dimensional steering.
arXiv Detail & Related papers (2025-09-12T16:14:59Z) - Error exponents of quantum state discrimination with composite correlated hypotheses [40.82628972269358]
We study the error exponents in quantum hypothesis testing between two sets of quantum states.<n>We introduce and compare two natural extensions of the quantum Hoeffding divergence and anti-divergence to sets of quantum states.
arXiv Detail & Related papers (2025-08-18T13:04:06Z) - Anomalous matrix product operator symmetries and 1D mixed-state phases [0.8883733362171032]
Generalized symmetries have emerged as a powerful organizing principle for exotic quantum phases.<n>We show that generalized symmetries can be used to probe anomalous quantum phases in open quantum systems.
arXiv Detail & Related papers (2025-04-23T18:00:00Z) - Improving absolute separability bounds for arbitrary dimensions [0.0]
Sufficient analytical conditions for separability in composite quantum systems are very scarce and only known for low-dimensional cases.
We use linear maps and their inverses to derive powerful analytical conditions, providing tight bounds and extremal points of the set of absolutely separable states.
arXiv Detail & Related papers (2024-10-29T18:00:04Z) - Classification of joint quantum measurements based on entanglement cost of localization [42.72938925647165]
We propose a systematic classification of joint measurements based on entanglement cost.
We show how to numerically explore higher levels and construct generalizations to higher dimensions and multipartite settings.
arXiv Detail & Related papers (2024-08-01T18:00:01Z) - Optimal Bell inequalities for qubit-qudit systems [44.99833362998488]
We evaluate the maximal Bell violation for a generic qubit-qudit system.<n>We show the impossibility of improving the amount of Bell-violation by embedding the qudit in a Hilbert space of larger dimension.
arXiv Detail & Related papers (2024-04-02T16:40:57Z) - Exactly Tight Information-Theoretic Generalization Error Bound for the
Quadratic Gaussian Problem [16.04977600068383]
We provide a new information-theoretic generalization error bound that is exactly tight (i.e., matching even the constant)
Most existing bounds are order-wise loose in this setting.
A refined bound is then proposed for decomposable loss functions, leading to a tight bound for the vector setting.
arXiv Detail & Related papers (2023-05-01T15:22:58Z) - An entropic uncertainty principle for mixed states [0.0]
We provide a family of generalizations of the entropic uncertainty principle.
Results can be used to certify entanglement between trusted parties, or to bound the entanglement of a system with an untrusted environment.
arXiv Detail & Related papers (2023-03-20T18:31:53Z) - Universal coding, intrinsic volumes, and metric complexity [3.4265828682659705]
In this assignment, the goal is to predict, or equivalently, a sequence of real-valued observations almost as well as the best distribution with mean-valued subsets of $mathbbRn.<n>As part of our analysis, we also characterize the minimax redundancy for a general constraint set.<n>We contrast our findings with classical results in information theory.
arXiv Detail & Related papers (2023-03-13T16:54:04Z) - On the Importance of Gradient Norm in PAC-Bayesian Bounds [92.82627080794491]
We propose a new generalization bound that exploits the contractivity of the log-Sobolev inequalities.
We empirically analyze the effect of this new loss-gradient norm term on different neural architectures.
arXiv Detail & Related papers (2022-10-12T12:49:20Z) - Relating measurement disturbance, information and orthogonality [0.38073142980732994]
In the general theory of quantum measurement, one associates a positive semidefinite operator on a $d$-dimensional Hilbert space to each of the $n$ possible outcomes of an arbitrary measurement.
This restriction allows us to more precisely state the quantum adage: information gain of a system is always accompanied by unavoidable disturbance.
We identify symmetric informationally complete quantum measurements as the unique quantum analogs of a perfectly informative and nondisturbing classical ideal measurement.
arXiv Detail & Related papers (2021-05-05T14:19:40Z) - Dimension Free Generalization Bounds for Non Linear Metric Learning [61.193693608166114]
We provide uniform generalization bounds for two regimes -- the sparse regime, and a non-sparse regime.
We show that by relying on a different, new property of the solutions, it is still possible to provide dimension free generalization guarantees.
arXiv Detail & Related papers (2021-02-07T14:47:00Z) - Failures of model-dependent generalization bounds for least-norm
interpolation [39.97534972432276]
We consider bounds on the generalization performance of the least-norm linear regressor.
For a variety of natural joint distributions on training examples, any valid generalization bound must sometimes be very loose.
arXiv Detail & Related papers (2020-10-16T16:30:05Z) - Generalized Sliced Distances for Probability Distributions [47.543990188697734]
We introduce a broad family of probability metrics, coined as Generalized Sliced Probability Metrics (GSPMs)
GSPMs are rooted in the generalized Radon transform and come with a unique geometric interpretation.
We consider GSPM-based gradient flows for generative modeling applications and show that under mild assumptions, the gradient flow converges to the global optimum.
arXiv Detail & Related papers (2020-02-28T04:18:00Z) - Sequences of lower bounds for entropic uncertainty relations from
bistochastic maps [0.0]
We show a strategy to derive sequences of lower bounds based on alternating sequences of measurements onto A and B.
The strategy can allow for an advantage both in the pure state and in the mixed state scenario.
arXiv Detail & Related papers (2019-12-30T16:35:45Z)
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.