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Related papers: Limits on the Observable Dynamics of Mixed States

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Via operator theoretic methods, we formalize the concentration phenomenon for a given observable `$r$' of a discrete time Markov chain with `$\mu_{\pi}$' as invariant ergodic measure, possibly having support on an unbounded state space. The…

Machine Learning · Computer Science 2023-06-01 Muhammad Abdullah Naeem , Miroslav Pajic

Given a bipartite quantum system represented by a tensor product of two Hilbert spaces, we give an elementary argument showing that if either component space is infinite-dimensional, then the set of nonseparable density operators is…

Quantum Physics · Physics 2009-10-31 Rob Clifton , Hans Halvorson

We present the conditions under which probabilistic error-free discrimination of mixed states is possible, and provide upper and lower bounds on the maximum probability of success for the case of two mixed states. We solve certain special…

Quantum Physics · Physics 2007-05-23 Terry Rudolph , Robert W. Spekkens , Peter Shipley Turner

In this paper, we introduce the concept of observability of targeted state variables for systems that may not be fully observable. For their estimation, we introduce and exemplify a deep filter, which is a neural network specifically…

Systems and Control · Electrical Eng. & Systems 2022-01-13 Wei Kang , Liang Xu , Hong Zhou

We study an optimized measurement that discriminates two mixed quantum states with maximum confidence for each conclusive result, thereby keeping the overall probability of inconclusive results as small as possible. When the rank of the…

Quantum Physics · Physics 2009-11-13 Ulrike Herzog

We investigate the asymptotic rates of entanglement transformations for bipartite mixed states by local operations and classical communication (LOCC). We analyse the relations between the rates for different transitions and obtain simple…

Quantum Physics · Physics 2009-10-19 Michal Horodecki , Aditi Sen De , Ujjwal Sen

The duality between controllability and observability enables methods developed for full-state control to be applied to full-state estimation, and vice versa. In applications in which control or estimation of all state variables is…

Systems and Control · Electrical Eng. & Systems 2023-09-26 Arthur N. Montanari , Chao Duan , Adilson E. Motter

We show that the quantum measurement known as the pretty good measurement can be used to identify an unknown quantum state picked from any set of $n$ mixed states that have pairwise fidelities upper-bounded by a constant below 1, given…

Quantum Physics · Physics 2019-11-11 Ashley Montanaro

Several concepts on the measure of observability, reachability, and robustness are defined and illustrated for both linear and nonlinear control systems. Defined by using computational dynamic optimization, these concepts are applicable to…

Optimization and Control · Mathematics 2009-07-17 Wei Kang , Liang Xu

We analyze the optimal unambiguous discrimination of two arbitrary mixed quantum states. We show that the optimal measurement is unique and we present this optimal measurement for the case where the rank of the density operator of one of…

Quantum Physics · Physics 2010-03-22 M. Kleinmann , H. Kampermann , D. Bruss

State convertibility is fundamental in the study of resource theory of quantum coherence. It is aimed at identifying when it is possible to convert a given coherent state to another using only incoherent operations. In this paper, we give a…

Quantum Physics · Physics 2024-10-29 Zhaofang Bai , Shuanping Du

Using the necessary and sufficient conditions, minimum error discrimination among two sets of similarity transformed equiprobable quantum qudit states is investigated. In the case that the unitary operators are generating sets of two…

Quantum Physics · Physics 2016-11-25 M. A. Jafarizadeh , Y. Mazhari Khiavi , Y. Akbari Kourbolagh

We derive a quantum speed limit for mixed quantum states using the stronger uncertainty relation for mixed quantum states and unitary evolution. We also show that this bound can be optimized over different choices of operators for obtaining…

Quantum Physics · Physics 2024-02-14 Shrobona Bagchi , Dimpi Thakuria , Arun Kumar Pati

We investigate generalized measurements, based on positive-operator-valued measures, and von Neumann measurements for the unambiguous discrimination of two mixed quantum states that occur with given prior probabilities. In particular, we…

Quantum Physics · Physics 2009-11-11 Ulrike Herzog , Janos A. Bergou

We give a bound on the mixing time of a uniformly ergodic, reversible Markov chain in terms of the spectral radius of the transition operator. This bound has been established previously in finite state spaces, and is widely believed to hold…

Probability · Mathematics 2014-05-02 Dawn B. Woodard

We derive dynamics-independent upper bounds on achievable quantum state transformations. Modeling the evolution as a joint unitary on the system and its environment, we show that the R\'enyi divergence between the initial system state and…

Quantum Physics · Physics 2025-08-20 Yoshihiko Hasegawa

While the detection of entanglement has been proved already to be quite a difficult task, experimental quantification of entanglement is even more challenging. In this work, we derive an analytical lower bound for the concurrence of a…

Quantum Physics · Physics 2011-04-07 Zhi-Hao Ma , Zhi-Hua Chen , Jing-Ling Chen

In this paper, the controllability and observability of linear multi-agent systems over matrix-weighted signed networks are analyzed. Firstly, the definition of equitable partition of matrix-weighted signed multi-agent system is given, and…

Optimization and Control · Mathematics 2022-04-05 Lanhao Zhao , Zhijian Ji , Yungang Liu , Chong Lin

Bounds analogous to entropic uncertainty relations allow one to design practical tests to detect quantum entanglement by a collective measurement performed on several copies of the state analyzed. This approach, initially worked out for…

Quantum Physics · Physics 2013-01-04 Łukasz Rudnicki , Zbigniew Puchała , Paweł Horodecki , Karol Życzkowski

We show that on exceeding a certain degree of mixedness (as quantified by the von Neumann entropy), entangled states become useless for teleporatation. By increasing the dimension of the entangled systems, this entropy threshold can be made…

Quantum Physics · Physics 2009-10-31 S. Bose , V. Vedral