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Related papers: Schmidt balls around the identity

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Unpredictability, or randomness, of the outcomes of measurements made on an entangled state can be certified provided that the statistics violate a Bell inequality. In the standard Bell scenario where each party performs a single…

Quantum Physics · Physics 2017-03-01 F. J. Curchod , M. Johansson , R. Augusiak , M. J. Hoban , P. Wittek , A. Acín

Not all entangled states can exhibit quantum steering, and determining whether a given entangled state is steerable is a crucial problem in quantum information theory. The main challenge lies in verifying the existence of a local…

Quantum Physics · Physics 2025-12-29 Yanning Jia , Fenzhuo Guo , Mengyan Li , Haifeng Dong , Fei Gao

Quantum entanglement is an important resource in many modern technologies, like quantum computation or quantum communication and information processing. Therefore, most interest is given to detect and quantify entangled states. Entanglement…

Quantum Physics · Physics 2026-05-12 Katarzyna Siudzińska

Quantum states may exhibit asymmetry with respect to the action of a given group. Such an asymmetry of states can be considered as a resource in applications such as quantum metrology, and it is a concept that encompasses quantum coherence…

In this article we study the expanding properties of random perturbations of contracting Lorenz maps satisfying the summability condition of exponent 1. Under general conditions on the maps and perturbation types, we prove stochastic…

Dynamical Systems · Mathematics 2026-04-10 Haoyang Ji

This article uses a combination of three ideas from simulation to establish a nearly optimal polynomial upper bound for the joint density of the stable process and its associated supremum at a fixed time on the entire support of the joint…

Probability · Mathematics 2023-11-20 Jorge González Cázares , Arturo Kohatsu Higa , Aleksandar Mijatović

We generalize the Schmidt-correlated states to multipartite systems. The related equivalence under SLOCC, the separability, entanglement witness, entanglement measures of negativity, concurrence and relative entropy are investigated in…

Quantum Physics · Physics 2009-11-13 Ming-Jing Zhao , Shao-Ming Fei , Zhi-Xi Wang

In this letter we have established the physical character of pure bipartite states with the same amount of entanglement in the same Schmidt rank that either they are local unitarily connected or they are incomparable. There exist infinite…

Quantum Physics · Physics 2008-05-20 Indrani Chattopadhyay , Debasis Sarkar

We investigate quantumness of spin-1 states, defined as the Hilbert-Schmidt distance to the convex hull of spin coherent states. We derive its analytic expression in the case of pure states as a function of the smallest eigenvalue of the…

Quantum Physics · Physics 2016-01-13 Fabian Bohnet-Waldraff , Daniel Braun , Olivier Giraud

In a recent paper, Rungta et. al. [Phys. Rev. A, 64, 042315, 2001] introduced a measure of mixed-state entanglement called the I-concurrence for arbitrary pairs of qudits. We find an exact formula for an entanglement measure closely related…

Quantum Physics · Physics 2009-11-07 Tobias J. Osborne

In a recent paper [Quantum 5, 552 (2021)], the authors proposed a framework for robustly self-testing steerable quantum assemblages. In this work, we apply their method to the scenario of self-testing two-qubit entangled quantum states. The…

Quantum Physics · Physics 2025-02-11 Chan-Ching Lien , Shin-Liang Chen

We introduce an experimental procedure for the detection of quantum entanglement of an unknown quantum state with as few measurements as possible. The method requires neither a priori knowledge of the state nor a shared reference frame…

We study various methods to generate ensembles of random density matrices of a fixed size N, obtained by partial trace of pure states on composite systems. Structured ensembles of random pure states, invariant with respect to local unitary…

Quantum Physics · Physics 2019-02-27 Karol Zyczkowski , Karol A. Penson , Ion Nechita , Benoit Collins

We describe various results related to the random distillation of multiparty entangled states - that is, conversion of such states into entangled states shared between fewer parties, where those parties are not predetermined. In previous…

Quantum Physics · Physics 2013-05-29 Ben Fortescue , Hoi-Kwong Lo

Given a complete, connected Riemannian manifold $ \mathbb{M}^n $ with Ricci curvature bounded from below, we discuss the stability of the solutions of a porous medium-type equation with respect to the 2-Wasserstein distance. We produce…

Analysis of PDEs · Mathematics 2022-07-29 Nicolò De Ponti , Matteo Muratori , Carlo Orrieri

A fundamental task in quantum information is to approximate a pure quantum state in terms of sparse states or, for a bipartite system, states of bounded Schmidt rank. The optimal deterministic approximation in each case is straightforward,…

Quantum Physics · Physics 2026-01-06 Aram W. Harrow , Angus Lowe , Freek Witteveen

The paper deals with minimax optimal statistical tests for two composite hypotheses, where each hypothesis is defined by a non-parametric uncertainty set of feasible distributions. It is shown that for every pair of uncertainty sets of the…

Statistics Theory · Mathematics 2018-04-17 Michael Fauss , Abdelhak M. Zoubir , H. Vincent Poor

The eigenstates of a quantum spin glass Hamiltonian with long-range interaction are examined from the point of view of localisation and entanglement. In particular, low particle sectors are examined and an anomalous family of eigenstates is…

Quantum Physics · Physics 2017-10-18 Arun Kannawadi , Auditya Sharma , Arul Lakshminarayan

The full Schmidt decomposition of spatiotemporally entangled states generated from spontaneous parametric down-conversion (SPDC) has not been carried out until now due to the immense computational complexity arising from the large…

Quantum Physics · Physics 2026-02-10 Rakesh Pradhan , Girish Kulkarni

We present an abstract formulation of the so-called Innsbruck-Hannover programme that investigates quantum correlations and entanglement in terms of convex sets. We present a unified description of optimal decompositions of quantum states…

Quantum Physics · Physics 2009-11-07 D. Bruss , J. I. Cirac , P. Horodecki , F. Hulpke , B. Kraus , M. Lewenstein , A. Sanpera