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Related papers: No relation for Wigner's friend

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The measurement problem is seen as an ambiguity of quantum mechanics, or, beyond that, as a contradiction within the theory: Quantum mechanics offers two conflicting descriptions of the Wigner's-friend experiment. As we argue in this note…

Quantum Physics · Physics 2019-12-09 Arne Hansen , Stefan Wolf

Quantum theory in its conventional formulation is notoriously subject to various measurement-related paradoxes, as exemplified by the "Schrodinger's Cat" and "Wigner's Friend" thought experiments. It has been shown, for example by…

Quantum Physics · Physics 2024-10-04 R. E. Kastner

In 1962, Eugene P. Wigner introduced a thought experiment that highlighted the incompatibility in quantum theory between unitary evolution and wave function reduction in a measurement. This work resulted in a class of thought experiments…

Quantum Physics · Physics 2021-05-19 Vinicius P. Rossi , Diogo O. Soares-Pinto

Exploiting the tension between the two dynamics of quantum theory (QT) in the Wigner's Friend thought experiment, we point out that the standard QT leads to inconsistency in observed probabilities of measurement outcomes between two…

Quantum Physics · Physics 2023-03-07 Shubhayan Sarkar , Debashis Saha

Extended Wigner's friend no-go theorems provide a modern lens for investigating the measurement problem, by making precise the challenges that arise when one attempts to model agents as dynamical quantum systems. Most such no-go theorems…

Quantum Physics · Physics 2025-11-18 Laurens Walleghem , Rafael Wagner , Yìlè Yīng , David Schmid

We celebrate this year hundred years of quantum mechanics but there is still no consensus regarding its interpretation and limitations. In this article we advocate the statistical contextual interpretation which is free of paradoxes. State…

Quantum Physics · Physics 2026-01-06 Marian Kupczynski

Quantum "states" are objective probability measures. Because their dependence on a time is not the time dependence of an evolving state, they are neither states of Nature nor "states of knowledge." There is no such thing as an evolving…

Quantum Physics · Physics 2007-05-23 Ulrich Mohrhoff

Two thought experiments are analyzed, revealing that the quantum state of the universe does not contain definitive evidence of the wavefunction collapse. The first thought experiment shows that unitary quantum evolution alone can account…

Quantum Physics · Physics 2017-09-08 Ovidiu Cristinel Stoica

In this paper, I attempt a personal account of my understanding of the measurement problem in quantum mechanics, which has been largely in the tradition of the Copenhagen interpretation. I assume that (i) the quantum state is a…

Quantum Physics · Physics 2015-07-21 Caslav Brukner

It is argued that the three assumptions of quantum collapse, one photon-one count, and relativity of simultaneity cannot hold together: Nonlocal correlations can depend on the referential frames of the beam-splitters but not of the…

Quantum Physics · Physics 2009-10-31 Antoine Suarez

I present a simple variant of the Schr\"odinger cat meets Wigner's friend thought experiment. If you are shocked by it, you have not understood quantum physics (no words are missing from this sentence).

Quantum Physics · Physics 2016-03-16 Vlatko Vedral

We show that, contrary to the claim by Kumar [Phys. Rev. A 96, 012332 (2017)], the quantum dual total correlation of an $n$-partite quantum state cannot be represented as the quantum relative entropy between $n-1$ copies of the quantum…

Quantum Physics · Physics 2024-01-02 Jaehak Lee , Gibeom Noh , Changsuk Noh , Jiyong Park

The renowned Local Friendliness no-go theorem demonstrates the incompatibility of quantum theory with the combined assumptions of Absoluteness of Observed Events - the idea that observed outcomes are singular and objective - and Local…

Quantum Physics · Physics 2026-05-18 Laurens Walleghem , Lorenzo Catani

Arguments have been raised that the system--observer cut of quantum mechanics can be shifted arbitrarily close to, or even into, the conscious observer. Here I show that this view leads to {\it observable} contradictions (despite our…

Quantum Physics · Physics 2007-05-23 Bernd A. Berg

The Semiotic Interpretation (SI) of QM pushes further the Von Neumann point of view that `experience only makes statements of this type: an observer has made a certain observation; and never any like this: a physical quantity has a certain…

Quantum Physics · Physics 2007-05-23 Jean Schneider

Using the remarkable mathematical construct of Eugene Wigner to visualize quantum trajectories in phase space, quantum processes can be described in terms of a quasi-probability distribution analogous to the phase space probability…

Quantum Physics · Physics 2013-01-29 Frank Kirtschig , Jorrit Rijnbeek , Jeroen van den Brink , Carmine Ortix

We present a simple model for stellar collapse and evaluate the quantum mechanical stress-energy tensor to argue that quantum effects do not play an important role for the collapse of astrophysical objects.

General Relativity and Quantum Cosmology · Physics 2018-01-17 Bruno Arderucio-Costa , William Unruh

In a joint paper Jeff Bub and Itamar Pitowski argued that the quantum state represents `the credence function of a rational agent [...] who is updating probabilities on the basis of events that occur'. In the famous thought experiment…

Quantum Physics · Physics 2019-02-01 Veronika Baumann , Časlav Brukner

In a recent paper, \.Zukowski and Markiewicz showed that Wigner's Friend (and, by extension, Schr\"odinger's Cat) can be eliminated as physical possibilities on purely logical grounds. I validate this result and demonstrate the source of…

Quantum Physics · Physics 2022-02-16 Andrew Knight

The notion of measurements is central for many debates in quantum mechanics. One critical point is whether a measurement can be regarded as an absolute event, giving the same result for any observer in an irreversible manner. Using ideas…

Quantum Physics · Physics 2023-02-20 Zhen-Peng Xu , Jonathan Steinberg , H. Chau Nguyen , Otfried Gühne