Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:quant-ph/9801056

Comments on Unruh's Paper

Henry Pierce Stapp

Published Jan 23, 1998• 0 citations
arXivHTMLPDF

Abstract

Unruh has commented upon my recent proof that certain predictions of quantum theory are incompatible with the assertion that no influence of any kind acts backward in time in any Lorentz frame. Unruh fails to make a necessary distinction between statements that assert the existence of values, and statements that assert the existence merely of correlations between possible values. Consequently his argument fails to show that my proof involves a tacit or hidden reality assumption that is alien to quantum theory.

DOI
10.48550/arxiv.quant-ph/9801056

Related papers

Comment on “Nonlocality, counterfactuals, and quantum mechanics”

Henry Pierce Stapp

A recent proof [H. P. Stapp, Am. J. Phys. 65, 300 (1997)], formulated in the symbolic language of modal logic, claims to show that contemporary quantum theory, viewed as a set of rules that allow us to calculate statistical predictions among certain kinds of observations, cannot be imbedded in any rational framework that conforms to the principles that (1) the experimenters' choices of which experiments they will perform can be considered to be free choices, (2) outcomes of measurements are unique, and (3) the free choices just mentioned have no backward-in-time effects of any kind. This claim is similar to Bell's theorem, but much stronger, because no reality assumption alien to quantum philosophy is used. The paper being commented on [W. Unruh, Phys. Rev. A 59, 126 (1999)] argues that some such reality assumption has been ``smuggled'' in. That argument is examined here and shown, I believe, to be defective.

Physical Review A•Sep 1, 1999•11 citations

Reply to Unruh

Henry Pierce Stapp

William Unruh has suggested (quant-ph/9710032) that a certain counterfactual statement in my recent nonlocality proof should be re-interpreted in a way that would block the proof. I give reason's why that statement should not be re-interpreted.

•Dec 19, 1997•3 citations

Reply to Unruh

Henry Pierce Stapp

William Unruh has suggested (quant-ph/9710032) that a certain counterfactual statement in my recent nonlocality proof should be re-interpreted in a way that would block the proof. I give reason's why that statement should not be re-interpreted.

arXiv:quant-ph/9712043•Dec 19, 1997•0 citations

Comments on ‘Nonlocal Influences and Possible Worlds’

Henry Pierce Stapp

Clifton, Butterfield, and Redhead [1989] have constructed two separate arguments that bear some resemblances to a proof of mine pertaining to the nonlocal character of quantum theory. Their arguments have flaws, which they point out. I explicate my proof by explaining in detail both how it differs logically from the two arguments they have constructed, and how it avoids the pitfalls of both.

The British Journal for the Philosophy of Science•Mar 1, 1990•7 citations

Reply to Unruh

Stapp, Henry P.

certain counterfactual statement in my recent nonlocality proof should be re-interpreted in a way that would block the proof.I give reason's why that statement should not be re-interpreted.

•Dec 19, 1997•0 citations

Nonlocality and Bohr's Reply to EPR

Henry Pierce Stapp

David Mermin's recent paper with the same title as this one makes it clear that his claim to have found a gap in my reasoning rests on his claim that my argument violates a criterion for meaningfulness of counterfactual statements that I myself had set down. I set down no such requirement. But I am willing to accept it as a conservative sufficient condition. This already entails, within my proof, that nature must have a deep structure that extends beyond what actually occurs. It imposes, without appeal to the notion of determinism or hidden variables, constraints connecting, at the macroscopic level, what did occur to what would have occurred if certain quantum choices had gone differently. All the statements in the proof have natural meanings within the context of an examination of that deep structure.

arXiv:quant-ph/9712036•Dec 17, 1997•1 citation
Unruh has commented upon my recent proof that certain predictions of quantum theory are incompatible with the assertion that no influence of any kind acts backward in time in any Lorentz frame. Unruh fails to make a necessary distinction between statements that assert the existence of values, and statements that assert the existence merely of correlations between possible values. Consequently his argument fails to show that my proof involves a tacit or hidden reality assumption that is alien to quantum theory.
A recent proof [H. P. Stapp, Am. J. Phys. 65, 300 (1997)], formulated in the symbolic language of modal logic, claims to show that contemporary quantum theory, viewed as a set of rules that allow us to calculate statistical predictions among certain kinds of observations, cannot be imbedded in any rational framework that conforms to the principles that (1) the experimenters' choices of which experiments they will perform can be considered to be free choices, (2) outcomes of measurements are unique, and (3) the free choices just mentioned have no backward-in-time effects of any kind. This claim is similar to Bell's theorem, but much stronger, because no reality assumption alien to quantum philosophy is used. The paper being commented on [W. Unruh, Phys. Rev. A 59, 126 (1999)] argues that some such reality assumption has been ``smuggled'' in. That argument is examined here and shown, I believe, to be defective.
David Mermin's recent paper with the same title as this one makes it clear that his claim to have found a gap in my reasoning rests on his claim that my argument violates a criterion for meaningfulness of counterfactual statements that I myself had set down. I set down no such requirement. But I am willing to accept it as a conservative sufficient condition. This already entails, within my proof, that nature must have a deep structure that extends beyond what actually occurs. It imposes, without appeal to the notion of determinism or hidden variables, constraints connecting, at the macroscopic level, what did occur to what would have occurred if certain quantum choices had gone differently. All the statements in the proof have natural meanings within the context of an examination of that deep structure.