Projects per year
Abstract
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 representation of knowledge of a (real or hypothetical) observer relative to her experimental capabilities; (ii) measurements have definite outcomes in the sense that only one outcome occurs; (iii) quantum theory is universal and the irreversibility of the measurement process is only "for all practical purposes". These assumptions are analyzed within quantum theory and their consistency is tested in Deutsch's version of the Wigner's friend gedanken experiment, where the friend reveals to Wigner whether she observes a definite outcome without revealing which outcome she observes. The view that holds the coexistence of the "facts of the world" common both for Wigner and his friend runs into the problem of the hidden variable program. The solution lies in understanding that "facts" can only exist relative to the observer.
Original language  English 

Title of host publication  Quantum [Un]Speakables II 
Subtitle of host publication  Half a Century of Bell's Theorem 
Editors  Reinhold Bertlmann, Anton Zeilinger 
Publisher  Springer International Publishing AG 
Pages  95117 
Number of pages  23 
Edition  1 
ISBN (Electronic)  9783319389875 
ISBN (Print)  9783319389851 
DOIs  
Publication status  Published  2017 
Publication series
Series  The Frontiers Collection 

ISSN  16123018 
Austrian Fields of Science 2012
 103025 Quantum mechanics
Keywords
 DECOHERENCE
 REDUCTION
 DYNAMICS
 SYSTEMS
 STATES
 Quantum Theory
 Measurement Problem
 Lyapunov Exponent
 Definite Outcome
 Quantum State
Projects
 3 Finished

Quantum Correlations and Quantum Communication Complexity
1/12/12 → 30/11/16
Project: Research funding

FoQuS III  P14: Simulation of strongly correlated quantum systems
Verstraete, F., Walther, P. & Paulovics, V.
1/01/09 → 31/12/18
Project: Research funding

CoQuS: Complex Quantum Systems
Aspelmeyer, M., Arndt, M. & Paulovics, V.
1/10/07 → 31/12/20
Project: Research funding