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Related papers: Protective measurements and the PBR theorem

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The PBR theorem gives insight into how quantum mechanics describes a physical system. This paper explores PBRs' general result and shows that it does not disallow the ensemble interpretation of quantum mechanics and maintains, as it must,…

Quantum Physics · Physics 2018-11-27 Anthony Rizzi

The theorem of Pusey, Barrett, and Rudolph proves that different quantum states describe different physical realities. Their proof is based on the construction of entanglement measurement bases of two, and more than two qbits. In this note,…

Quantum Physics · Physics 2014-01-03 C. Moseley

Pusey, Barrett and Rudolph (PBR) have recently proven an important new theorem in the foundations of quantum mechanics. Here we propose alternative experimental protocols which lead to the PBR result for a special case and a weaker PBR-like…

Quantum Physics · Physics 2013-05-30 D. J. Miller

In the above paper [1], it is claimed that Bohm's mechanics can be challenged by a simple gedanken experiment involving a protecting measurement. Here we show that this gedanken experiment can be justified without problem and without…

Quantum Physics · Physics 2009-11-13 A. Drezet

Quantum mechanics, one of the keystones of modern physics, exhibits several peculiar properties, differentiating it from classical mechanics. One of the most intriguing is that variables might not have definite values. A complete quantum…

We generalize protective measurement for protective joint measurement of several observables. The merit of joint protective measurement is the determination of the eigenstates of an unknown Hamiltonian rather than the determination of…

Quantum Physics · Physics 2014-02-03 Lajos Diósi

The Pusey-Barrett-Rudolph theorem has recently provoked a lot of discussion regarding the reality of the quantum state. In this article we focus on a property called antidistinguishability, which is a main component in constructing the…

Quantum Physics · Physics 2018-08-13 Teiko Heinosaari , Oskari Kerppo

We compare the performance of protective quantum measurements to that of standard projective measurements. Performance is quantified in terms of the uncertainty in the measured expectation value. We derive an expression for the relative…

Quantum Physics · Physics 2024-09-19 Maximilian Schlosshauer

Classical ergodicity retains its meaning in the quantum realm when the employed measurement is protective. This unique measuring technique is reexamined in the case of post-selection, giving rise to novel insights studied in the Heisenberg…

Quantum Physics · Physics 2014-03-06 Yakir Aharonov , Eliahu Cohen

$\psi$-epistemic interpretations of quantum theory maintain that quantum states only represent incomplete information about the physical states of the world. A major motivation for this view is the promise to provide a reasonable account of…

Quantum Physics · Physics 2020-03-18 Joshua B. Ruebeck , Piers Lillystone , Joseph Emerson

The analysis of Pusey, Barrett and Rudolph aims to show there can be no objective physical reality which underlies, and is more general than, the state vector. But there appears to be a gap in their reasoning. To show their result, they use…

Quantum Physics · Physics 2015-11-18 Casey Blood

According to quantum theory, the outcomes of future measurements cannot (in general) be predicted with certainty. In some cases, even with a complete physical description of the system to be measured and the measurement apparatus, the…

Quantum Physics · Physics 2012-07-16 Terence E. Stuart , Joshua A. Slater , Roger Colbeck , Renato Renner , Wolfgang Tittel

$\Psi$-epistemic models of quantum mechanics imply that the quantum state does not correspond to physical reality, but instead reflects the observer's knowledge of the underlying quantum system. The epistemic view of the quantum state has…

Quantum Physics · Physics 2026-05-14 İnanç Şahin

Applications of quantum mechanics have led to many successful predictions and explanations of puzzling phenomena, and we now apply quantum mechanics to gain, process, and communicate information in novel ways. We can understand quantum…

Quantum Physics · Physics 2026-04-03 Richard Healey

The Pusey-Barrett-Rudolph (PBR) no-go theorem provides an argument for the reality of the quantum state by ruling out {\psi}-epistemic ontological theories, in which the quantum state is of a statistical nature. It applies under an…

Quantum Physics · Physics 2017-02-28 Shane Mansfield

Here we show that, in principle it is possible to clone (measure) a single arbitrary unknown quantum state of a spin-$\frac{1}{2}$ particle (an electron) with arbitrary precision and with success probability tending to one, using protective…

Quantum Physics · Physics 2015-04-24 C. S. Sudheer Kumar

Measurement is a fundamental notion in the usual approximate quantum mechanics of measured subsystems. Probabilities are predicted for the outcomes of measurements. State vectors evolve unitarily in between measurements and by reduction of…

General Relativity and Quantum Cosmology · Physics 2014-01-14 James B. Hartle

The PBR theorem has been hailed as one of the most important theorems in the foundations of quantum mechanics (QM), , cf. E. Samuel Reich, "Quantum theorem shakes foundations", Nature (2011). Here we argue that the special measurement, used…

General Physics · Physics 2023-07-12 Marcoen J. T. F. Cabbolet

I argue that we have good reason for being realist about quantum states. Though a research programme of attempting to construct a plausible theory that accounts for quantum phenomena without ontic quantum states is well-motivated, that…

Quantum Physics · Physics 2019-11-26 Wayne C. Myrvold

In the distribution of quantum states over a long distance, not only are quantum states corrupted by interactions with an environment but also a measurement setting should be re-aligned such that detection events can be ensured for the…