Physics and Astronomy - Quantum Nano Seminar - Flavio Del Santo, Univ. of Vienna

Dartmouth Events

Physics and Astronomy - Quantum Nano Seminar - Flavio Del Santo, Univ. of Vienna

Title: "Are There Observer-Independent Outcomes in Quantum Theory?"

Thursday, February 28, 2019
4:00pm-5:00pm
Wilder 202
Intended Audience(s): Public
Categories: Lectures & Seminars
Abstract: Recent modifications of the Wigner's friend Gedankenexperiment, which involve multiple agents and their combination into Bell-type arguments, have led to sharpen the fundamental problem of the measurement in quantum theory. In particular, a no-go theorem formulated by Brukner [1] allows to claim that there are “no facts of the world per se, but only relative to an observer”. Such a proposal has been recently criticised by Healey [2], who, despite pursuing the same program of limiting the objectivity of outcomes, proposed a new version of the gedankenexperiment that allegedly solves the reised issues. However, I will show [4] that Healey’s proposal suffers from the main criticism, that the computed correlation functions entering a Bell's inequality are in principle experimentally inaccessible, and hence the author's claim is not verifiable in principle. I will discuss perspectives for fixing that by adapting the proposed protocol and show that this, however, makes Healey's argument virtually equivalent to other previous similar proposal that he explicitly criticises.
 
[1] C. Brukner, "A no-go theorem for observer independent facts," Entropy 20, 350 (2018).
[2] R. Healey, "Quantum Theory and the Limits of Objectivity," to appear in Found. Phys. (2018), https://arxiv.org/abs/1807.00421.
[3] V. Baumann, F. Del Santo, Č. Brukner. 2019. “Comment on Healey’s ‘Quantum Theory and the limits of Objectivity’”. In preparation.
For more information, contact:
Tressena Manning
603-646-2854

Events are free and open to the public unless otherwise noted.