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Related papers: The complexity of compatible measurements

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The existence of maximally incompatible quantum observables in the sense of a minimal joint measurability region is investigated. Employing the universal quantum cloning device it is argued that only infinite dimensional quantum systems can…

Quantum Physics · Physics 2014-06-06 Teiko Heinosaari , Jussi Schultz , Alessandro Toigo , Mario Ziman

Incompatible measurements, i.e., measurements that cannot be simultaneously performed, are necessary to observe nonlocal correlations. It is natural to ask, e.g., how incompatible the measurements have to be to achieve a certain violation…

Quantum Physics · Physics 2021-05-27 Shin-Liang Chen , Nikolai Miklin , Costantino Budroni , Yueh-Nan Chen

Pivotal within quantum physics, the concept of quantum incompatibility is generally related to algebraic aspects of the formalism, such as commutation relations and unbiasedness of bases. Recently, the concept was identified as a resource…

Quantum Physics · Physics 2020-12-24 E. Martins , M. F. Savi , R. M. Angelo

Relevance of key quantum information measures for analysis of quantum systems is discussed. It is argued that possible ways of measuring quantum information are based on compatibility/incompatibility of the quantum states of a quantum…

Quantum Physics · Physics 2015-06-26 B. A. Grishanin , V. N. Zadkov

The existence of incompatible measurements is a fundamental phenomenon having no explanation in classical physics. Intuitively, one considers given measurements to be incompatible within a framework of a physical theory, if their…

Quantum Physics · Physics 2015-08-27 Teiko Heinosaari , Jukka Kiukas , Daniel Reitzner

In practical applications like quantum sensing and quantum imaging, there is often a necessity to estimate multiple parameters simultaneously. Although the ultimate precision limits for single-parameter estimation are well established, the…

The measurement postulate of quantum theory stands in conflict with the laws of thermodynamics and has evoked debate regarding what actually constitutes a measurement. With the help of modern quantum statistical mechanics, we take the first…

Quantum Physics · Physics 2025-12-16 Emanuel Schwarzhans , Felix C. Binder , Marcus Huber , Maximilian P. E. Lock

We argue that it is fundamentally impossible to recover information about quantum superpositions when a system has interacted with a sufficiently large number of degrees of freedom of the environment. This is due to the fact that gravity…

Quantum Physics · Physics 2010-01-07 Rodolfo Gambini , Luis Pedro Garcia Pintos , Jorge Pullin

Recently a problem concerning the equivalence of joint measurability and coexistence of quantum observables was solved [15]. In this paper we generalize two known joint measurability results from sharp observables to the class of extreme…

Quantum Physics · Physics 2015-08-19 Erkka Haapasalo , Juha-Pekka Pellonpää , Roope Uola

Some quantum measurements can not be performed simultaneously, i.e. they are incompatible. Here we show that every set of incompatible measurements provides an advantage over compatible ones in a suitably chosen quantum state discrimination…

Quantum Physics · Physics 2019-04-10 Paul Skrzypczyk , Ivan Šupić , Daniel Cavalcanti

The term "measurement" in quantum theory (as well as in other physical theories) is ambiguous: It is used to describe both an experience - e.g., an observation in an experiment - and an interaction with the system under scrutiny. If doing…

Quantum Physics · Physics 2019-04-03 Arne Hansen , Stefan Wolf

We consider the problem of certifying measurement incompatibility in a prepare-and-measure (PM) scenario. We present different families of sets of qubit measurements which are incompatible, but cannot lead to any quantum over classical…

Quantum Physics · Physics 2025-09-22 Sophie Egelhaaf , Jef Pauwels , Marco Túlio Quintino , Roope Uola

Joint or simultaneous measurements of non-commuting quantum observables are possible at the cost of increased unsharpness or measurement uncertainty. Many different criteria exist for defining what an "optimal" joint measurement is, with…

It is well known that when two or more quantum measurements suffer from imperfections they may lose their incompatibility. For a quantum system of finite dimension d we study the incompatibility of all projective measurements subjected to…

Quantum Physics · Physics 2025-02-11 Pavel Sekatski

Every theory of information, including classical and quantum, can be studied in the framework of operational probabilistic theories--where the notion of test generalizes that of quantum instrument, namely a collection of quantum operations…

Quantum Physics · Physics 2023-05-26 Giacomo M. D'Ariano , Paolo Perinotti , Alessandro Tosini

Basic quantum information measures involved in the information analysis of quantum systems are considered. It is shown that the main quantum information measurement methods depend on whether the corresponding quantum events are compatible…

Quantum Physics · Physics 2007-05-23 B. A. Grishanin , V. N. Zadkov

The existence of observables that are incompatible or not jointly measurable is a characteristic feature of quantum mechanics, which lies at the root of a number of nonclassical phenomena, such as uncertainty relations, wave--particle dual…

Quantum Physics · Physics 2015-11-17 Huangjun Zhu

Recently, it has been stated that single-world interpretations of quantum theory are logically inconsistent. The claim is derived from contradicting statements of agents in a setup combining two Wigner's-friend experiments. Those statements…

Quantum Physics · Physics 2016-11-04 Veronika Baumann , Arne Hansen , Stefan Wolf

The measurement process of observables in a quantum system comes out to be an unsovable problem which started in the early times of the development of the theory. In the present note we consider the measured system part of an open system…

Quantum Physics · Physics 2023-12-21 Jean Richert , Tarek Khalil

Measurement incompatibility has proved to be an important resource for quantum information processing. In this work, we present an operational approach that leverages classical operations on the inputs (pre-processing) and outputs…

Quantum Physics · Physics 2026-01-16 Arun Kumar Das , Saheli Mukherjee , Debashis Saha , Debarshi Das , A. S. Majumdar