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We consider bipartite quantum state discrimination using positive-partial-transpose measurements and show that minimum-error discrimination by positive-partial-transpose measurements is closely related to entanglement witness. By using the…

Quantum Physics · Physics 2023-05-18 Donghoon Ha , Jeong San Kim

Equivalence between Positive Partial Transpose (PPT) entanglement and bound entanglement is a long-standing open problem in quantum information theory. So far limited progress has been made, even on the seemingly simple case of Werner…

Quantum Physics · Physics 2024-07-02 Si-Yuan Qi , Geni Gupur , Yu-Chun Wu , Guo-Ping Guo

We apply random matrix and free probability techniques to the study of linear maps of interest in quantum information theory. Random quantum channels have already been widely investigated with spectacular success. Here, we are interested in…

Quantum Physics · Physics 2019-02-27 Benoit Collins , Patrick Hayden , Ion Nechita

A central problem in quantum resource theory is to give operational meaning to quantum resources that can provide clear advantages in certain physical tasks compared to the convex set of resource-free states. We propose to extend this basic…

Quantum Physics · Physics 2024-12-30 Sunho Kim , Chunhe Xiong , Junde Wu

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

We introduce the resource quantifier of weight of resource for convex quantum resource theories of states with arbitrary resources. We show that it captures the advantage that a resourceful state offers over all possible free states, in the…

Quantum Physics · Physics 2020-09-16 Andrés F. Ducuara , Paul Skrzypczyk

Quantum complexity is emerging as a key property of many-body systems, including black holes, topological materials, and early quantum computers. A state's complexity quantifies the number of computational gates required to prepare the…

This manuscript introduces a computationally efficient method to calculate the nonlinearity of a quantum feature map, as well as a method for determining whether a quantum feature map will have a high concentration of quantum states. The…

Quantum Physics · Physics 2025-10-31 Andrew Vlasic , Payal Solanki , Anh Pham

Entanglement witness is an effective method to detect entanglement in unknown states without doing full tomography. One of the most widespread schemes of witnessing entanglement is measuring its fidelity with respect to a pure entangled…

Quantum Physics · Physics 2021-03-19 Yongtao Zhan , Hoi-Kwong Lo

Bipartite entanglement entropies, calculated from the reduced density matrix of a subsystem, provide a description of the resources available within a system for performing quantum information processing. However, these quantities are not…

Quantum Physics · Physics 2014-02-06 Robert N. C. Pfeifer

We show how to verify the metrological usefulness of quantum states based on the expectation values of an arbitrarily chosen set of observables. In particular, we estimate the quantum Fisher information as a figure of merit of metrological…

Quantum Physics · Physics 2017-04-25 Iagoba Apellaniz , Matthias Kleinmann , Otfried Gühne , Geza Toth

The entanglement witness and the entropy uncertainty are investigated by using the pseudomode theory for the open two-atom system under the quantum Zeno effect. The results show that, only when the two spectrums satisfy strong coupling with…

Quantum Physics · Physics 2023-01-24 Rongfang Liu , Hong-Mei Zou , Jianhe Yang , Danping Lin

In the framework of Algebraic Quantum Field Theory, several operator algebraic notions of entanglement entropy can be associated with any pair of causally disjoint spacetime regions $\mathcal{S}_A$ and $\mathcal{S}_B$ with positive relative…

Quantum Physics · Physics 2026-01-28 Lorenzo Panebianco , Benedikt Wegener

We derive the strong subadditivity of the von Neumann entropy with a strict lower bound dependent on the distribution of quantum correlation in the system. We investigate the structure of states saturating the bounded subadditivity and…

Quantum Physics · Physics 2022-05-26 L. R. S. Mendes , M. C. de Oliveira

We present an unifying approach to the quantification of entanglement based on entanglement witnesses, which includes several already established entanglement measures such as the negativity, the concurrence and the robustness of…

Quantum Physics · Physics 2007-05-23 Fernando Guadalupe Santos Lins Brandao

It is well-known that von Neumann entropy is nonmonotonic unlike Shannon entropy (which is monotonically nondecreasing). Consequently, it is difficult to relate the entropies of the subsystems of a given quantum state. In this paper, we…

Quantum Physics · Physics 2011-04-07 Pradeep Sarvepalli

Finding the minimal relative entropy of two quantum states under semidefinite constraints is a pivotal problem located at the mathematical core of various applications in quantum information theory. An efficient method for providing…

Quantum Physics · Physics 2026-02-02 Gereon Koßmann , René Schwonnek

Which quantum phenomena are advantageous for information processing tasks? By classifying quantum states as resourceful versus non-resourceful, or free, the mathematical formalism of quantum resource theories helps to address such…

Quantum Physics · Physics 2025-09-22 Leah Turner , Madalin Guta , Gerardo Adesso

We analyze, for a general concave entropic form, the associated conditional entropy of a quantum system A+B, obtained as a result of a local measurement on one of the systems (B). This quantity is a measure of the average mixedness of A…

Quantum Physics · Physics 2013-12-16 N. Gigena , R. Rossignoli

Applying the theory of self-adjoint extensions of Hermitian operators to Koopman von Neumann classical mechanics, the most general set of probability distributions is found for which entropy is conserved by Hamiltonian evolution. A new…

Statistical Mechanics · Physics 2019-06-24 Gerard McCaul , Alexander Pechen , Denys I. Bondar