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Related papers: Conditional Action and imperfect Erasure of Qubits

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We reframe the EPR argument through an operational lens, replacing the notion of fixed "elements of reality" with context-indexed conditional states - what's often referred to as a measurement assemblage. This move deliberately sidesteps…

Quantum Physics · Physics 2026-01-06 Mikołaj Sienicki , Krzysztof Sienicki

Acausal features of quantum electrodynamic processes are discussed. While these processes are not present for the classical electrodynamic theory, in the quantum electrodynamic theory, acausal processes are well known to exist. For example,…

Quantum Physics · Physics 2007-05-23 A. Widom , Y. N. Srivastava , E. Sassaroli

There exists a paradox in quantum field theory: substituting a field configuration which solves a subset of the field equations into the action and varying it is not necessarily equivalent to substituting that configuration into the…

High Energy Physics - Theory · Physics 2009-11-11 Zhong Chao Wu

Quantum entanglement is analyzed thoroughly in the case of the ground and lowest states of two-electron axially symmetric quantum dots under a perpendicular magnetic field. The individual-particle and the center-of-mass representations are…

Quantum Physics · Physics 2015-12-01 N. S. Simonovic , R. G. Nazmitdinov

We report the results of an experiment that searches for causal non-linear state-dependent terms in quantum field theory. Our approach correlates a binary macroscopic classical voltage with the outcome of a projective measurement of a…

We introduce a reversible theory of exact entanglement manipulation by establishing a necessary and sufficient condition for state transfer under trace-preserving transformations that completely preserve the positivity of partial transpose…

Quantum Physics · Physics 2023-12-08 Xin Wang , Yu-Ao Chen , Lei Zhang , Chenghong Zhu

We present a detailed account of quantum state estimation by joint maximization of the likelihood and the entropy. After establishing the algorithms for both perfect and imperfect measurements, we apply the procedure to data from simulated…

Based on the concepts of the quantum field theory of virtual photons as quanta of electromagnetic interaction, we discuss the physical content of the phenomena underlying the principle of quantum uncertainties. We consider the features of…

Quantum Physics · Physics 2022-08-04 V. N. Murzin , L. Yu. Shchurova

The concept of entropy and the correct application of the Second Law of thermodynamics are essential in order to understand the reason why quantum error correction is thermodynamically possible and no violation of the Second Law occurs…

Quantum Physics · Physics 2015-06-16 Carlo Cafaro , Peter van Loock

A colloquial interpretation of entropy is that it is the knowledge gained upon learning the outcome of a random experiment. Conditional entropy is then interpreted as the knowledge gained upon learning the outcome of one random experiment…

Quantum Physics · Physics 2024-11-20 Gilad Gour , Mark M. Wilde , Sarah Brandsen , Isabelle Jianing Geng

Universality of quantum mechanics -- its applicability to physical systems of quite different nature and scales -- indicates that quantum behavior can be a manifestation of general mathematical properties of systems containing…

Mathematical Physics · Physics 2010-11-03 Vladimir V. Kornyak

In the quantum regime, the third law of thermodynamics implies the unattainability of pure states. As shown recently, such unattainability implies that a unitary interaction between the measured system and a measuring apparatus can never…

Quantum Physics · Physics 2023-02-09 M. Hamed Mohammady , Takayuki Miyadera

An analysis of quantum measurement is presented that relies on an information-theoretic description of quantum entanglement. In a consistent quantum information theory of entanglement, entropies (uncertainties) conditional on measurement…

Quantum Physics · Physics 2008-02-03 N. J. Cerf , C. Adami

Quantum phase transitions occur at zero temperature when some non-thermal control-parameter like pressure or chemical composition is changed. They are driven by quantum rather than thermal fluctuations. In this review we first give a…

Statistical Mechanics · Physics 2017-09-27 Thomas Vojta

We demonstrate the conditional reversal of a weak (partial-collapse) quantum measurement on a photonic qubit. The weak quantum measurement causes a nonunitary transformation of a qubit which is subsequently reversed to the original state…

Quantum Physics · Physics 2015-05-13 Yong-Su Kim , Young-Wook Cho , Young-Sik Ra , Yoon-Ho Kim

We derive the theory of open quantum system dynamics intervened by a series of nonselective measurements. We analyze the cases of time independent and time dependent Hamiltonian dynamics in between the measurements and find the approximate…

Quantum Physics · Physics 2018-01-17 Sergey N. Filippov

Exploring quantum phenomena beyond predictions of any classical model has fundamental importance to understand the boundary of classical and quantum descriptions of nature. As a typical property that a quantum system behaves distinctively…

Non Gaussian states and processes are useful resources in quantum information with continuous variables. An experimentally accessible criterion has been proposed to measure the degree of non Gaussianity of quantum states, based on the…

A theory of quantum measurement was introduced some time ago that was based on the notion of the so-called separation status. This separation status had a spatial, local character, so that the theory worked only in special cases.…

Quantum Physics · Physics 2016-06-14 Petr Hajicek

Theory of quantum measurements is often classified as decision theory. An event in decision theory corresponds to the measurement of an observable. This analogy looks clear for operationally testable simple events. However, the situation is…

Quantum Physics · Physics 2015-06-24 V. I. Yukalov , D. Sornette