@ruth
active 1 month, 1 week ago
Ruth Kastner replied to the topic Is there an inconsistent friend? in the forum Workshop on Wigner’s Friend 2018 1 year, 3 months ago
This is an interesting situation: assessments of the bearing and validity of the FR proof greatly depend on what quantum theory itself is taken to be. For example, Editor has referred to two different forms of QT:
(1) QT with collapse postulate — call it “QTCP”
(2) QT without collapse postulate — call it “QTNCP”
…and has noted, based on…[Read more] 
Ruth Kastner replied to the topic Is there an inconsistent friend? in the forum Workshop on Wigner’s Friend 2018 1 year, 3 months ago
I would just comment here that Brukner’s formulation of the measurement problem presupposes an epistemic interpretation of the quantum state relative to a particular observer. So his analysis and conclusions do not apply to cases in which the quantum state ontologically refers. In particular, he concludes that facts are necessarily…[Read more]

Ruth Kastner started the topic How we avoid getting to the Wigner's Friend situation in the first place in the forum Workshop on Wigner’s Friend 2018 1 year, 3 months ago
The Wigner’s Friend scenario was created to amplify the measurement problem as illustrated by Schrodinger’s Cat. We don’t encounter a Wigner’s Friend dilemma in the first place if we have a means of delineating, in physical terms, what constitutes ‘measurement’ (where that is described by von Neumann’s Process 1 nonunitary transition)…[Read more]

Ruth Kastner replied to the topic Is there an inconsistent friend? in the forum Workshop on Wigner’s Friend 2018 1 year, 3 months ago
Dear Editor: Should I start a new topic to address the measurement problem, which is what is being illustrated by the Wigner’s Friends scenario? In particular, we don’t encounter a Wigner’s Friend dilemma in the first place if we have a means of delineating, in physical terms, what constitutes ‘measurement’ (where that is described by von…[Read more]

Ruth Kastner posted a new activity comment 1 year, 3 months ago
I would just note that RTI is not subject to the recent ‘nogo’ proofs since it does not assert that quantum states are universally applicable; rather it has a natural limiting criterion for the applicability of quantum states. It particular, neither the Geiger counter nor the cat nor Wigner nor his friend (understood as spacetimelocatable obj…[Read more]

Ruth Kastner posted an update in the group Workshop on Wigner’s Friend 2018 1 year, 3 months ago
May I add as a relevant reference:
Kastner, R. E. On the Status of the Measurement Problem: Recalling the Relativistic Transactional Interpretation
International Journal of Quantum Foundations, 2017,
Volume 4, Issue 1, pages 128141 
Ruth Kastner joined the group 2018 Workshop on Wigner’s Friend 1 year, 3 months ago

Ruth Kastner started the topic TI: Derivation of the Born Rule for Radiative Processes in the forum Retrocausal theories 1 year, 8 months ago
The Transactional Interpretation involves advanced field states and is therefore considered a form of a ‘retrocausal’ interpretation, although in the relativistic development of TI (RTI), the advanced states (as well as the triggering retarded states) are complex objects and are subempirical (i.e., not spacetime processes). It is only the…[Read more]

Ruth Kastner started the topic The Transactional Interpretation is a Collapse Theory in the forum Collapse theories 1 year, 8 months ago
It is not widely recognized that the Transactional Interpretation (TI) is a collapse theory; however, it is one that does not make ad hoc changes to the Schrodinger equation. Collapse is accounted for in TI by taking into account absorber response as a physical process (in the socalled ‘absorber theory’ of fields). Absorber response provides the…[Read more]

Ruth Kastner commented on the post, 2019 International Workshop: Beyond Bell’s theorem 1 year, 8 months ago
For the 2018 Workshop, I would like to discuss the Relativistic Transactional Interpretation, specifically the explicit derivation of the Born Rule for radiative processes as presented in my recent paper with John Cramer (https://arxiv.org/abs/1711.04501).
It appears clear that TI and RTI provide a physical account of measurement as well as a…[Read more]

Ruth Kastner wrote a new post, Topic for 2018 Int’l Workshop on Quantum Foundations 1 year, 8 months ago
I would like to discuss the Relativistic Transactional Interpretation, specifically the explicit derivation of the Born Rule for radiative processes as presented in my recent paper with John Cramer (https://arxiv.org/abs/1711.04501).
It appears clear that TI and RTI provide a physical account of measurement as well as a physical derivation of the Born Rule. Previous objections to TI (such as that of Maudlin) have been unambiguously resolved and/or nullified (e.g., https://arxiv.org/abs/1610.04609). Thus, TI is still perfectly viable and provides longsought solutions to pressing problems in quantum theory regarding the need for a physically grounded definition of ‘measurement’ and the source of the Born Rule (as well as a solution to the consistency problems for QFT as reflected in Haag’s theorem, http://www.ijqf.org/archives/2004). Curiously, however, TI is still not generally recognized as among the ‘mainstream’ approaches. I look forward to discussing with other IJQF members why that might be. Is it the apparent “action at a distance” of the directaction theory that is offputting? Is it because both Wheeler and Feynman abandoned their theory (though Wheeler was later advocating it again in 2003)? Comments welcome.

Ruth Kastner commented on the post, Taking Heisenberg’s Potentia Seriously 1 year, 10 months ago
Thanks Dr. Sarfatti for your comments. The authors in no way assert that this matter is settled, but simply propose what we believe is a fruitful avenue for exploration.

Ruth Kastner commented on the post, Violation of the Born Rule: Implications for Macroscopic Fields. 1 year, 10 months ago
Referees agreed with arguments in this paper and it has been accepted. Indeed there is no inconsistency; if there is no Born Rule violation in the limit Dr. Sarfatti discusses, then there is also no ‘real world’ applicability of such Born Rule violations as he has previously argued. The paper simply shows that real world Born Rule violations lead…[Read more]

Ruth Kastner wrote a new post, Submission: Quantifying Absorption in the Transactional Interpretation 1 year, 11 months ago
R. E. Kastner, John G. Cramer 3 Feb. 2018
Abstract: The Transactional Interpretation offers a solution to the measurement problem by identifying specific physical conditions precipitating the nonunitary […]

editor and Ruth Kastner are now friends 2 years ago

elpadrino and Ruth Kastner are now friends 2 years ago

Valia Allori and Ruth Kastner are now friends 2 years ago

Ruth Kastner wrote a new post, New Submission: Reply to Marchildon: absorption and nonunitarity remain welldefined in the Relativistic Transactional Interpretation 2 years, 1 month ago
I rebut some erroneous statements and attempt to clear up some misunderstandings in a recent set of critical remarks by Marchildon regarding the Relativistic Transactional Interpretation (RTI) in this Journal, showing that his negative conclusions regarding the transactional model are illfounded.
Paper link here: Reply to LM IJQF4

Ruth Kastner commented on the post, Remarks on the Relativistic Transactional Interpretation of Quantum Mechanics 2 years, 1 month ago
Followup regarding the issue of a physically meaningful probability: the essential point is that the full physical probability of a nonunitary measurement transition is always given by the square of the [coupling constant times the transition amplitude] for the relevant transition. And this is always timedependent (i.e. a decay rate applying to…[Read more]

Ruth Kastner commented on the post, Remarks on the Relativistic Transactional Interpretation of Quantum Mechanics 2 years, 1 month ago
Prof. Marchildon’s objections are based on numerous misunderstandings, which I’ve tried to correct in emails (apparently unsuccessfully). I will try again here.
First, he is still looking for empirical predictions from RTI that differ from standard quantum theory. But as I’ve repeatedly noted in an email exchange with him, RTI is empirically…[Read more]  Load More
I would just note that RTI is not subject to the recent ‘nogo’ proofs since it does not assert that quantum states are universally applicable; rather it has a natural limiting criterion for the applicability of quantum states. It particular, neither the Geiger counter nor the cat nor Wigner nor his friend (understood as spacetimelocatable obj…[Read more]