The ‘Delayed Choice Quantum Eraser’ Neither Erases Nor Delays

The so-called 'quantum eraser' is an experiment that has prompted widespread confusion. In fact, it is nothing more than a photonic version of the EPR experiment. Nothing is erased, and there is no necessary retrocausation or 'temporal nonlocality,' beyond standard EPR correlations. I attempt to clear up the confusion in this paper, which has now … Continue reading The ‘Delayed Choice Quantum Eraser’ Neither Erases Nor Delays

Important New Book on Math Education

Bernice Kastner is a math educator whose innovative approach has helped to transform classrooms and enable many students to gain confidence and mastery in math. (She also happens to be my mother.) Her new book, The Role of Language in Teaching Children Math, is now out: https://www.austinmacauley.com/us/book/role-language-teaching-children-math From the publisher: "It can be difficult to … Continue reading Important New Book on Math Education

A critical look at popular ‘retrocausation’ claims. Do they hold up?

In this publication, I address popular uses of the term 'retrocausation' in connection with quantum theory, and find that there is much that needs to be corrected and clarified. Much of the discussion in the literature on this topic involves inconsistencies and equivocation about what retrocausation really is, and about what it can do.  In … Continue reading A critical look at popular ‘retrocausation’ claims. Do they hold up?

Why “making sense of quantum theory” by denying that theories are about the world does not really work

This post is a critique of an interpretational approach to quantum theory known as "Qbism."  Qbism is currently advocated primarily by Fuchs, Mermin, and Schack.  Here, I discuss a little-known but powerful and important argument from Joe Henson regarding Qbism. Henson's argument discloses a crucial fallacy in Qbism's claim to "save locality" in quantum theory; … Continue reading Why “making sense of quantum theory” by denying that theories are about the world does not really work

Is There Really “Retrocausation” in Time-Symmetric Approaches to Quantum Mechanics?

This is a preprint version of this paper: AIP Conference Proceedings 1841, 020002 (2017) R. E. Kastner Abstract. Time-symmetric interpretations of quantum theory are often presented as featuring "retrocausal" effects in addition to the usual forward notion of causation. This paper examines the ontological implications of certain time- symmetric theories, and finds that no dynamical notion … Continue reading Is There Really “Retrocausation” in Time-Symmetric Approaches to Quantum Mechanics?

Paper with John Cramer on Absorption in TI

I recently co-authored a paper with Transactional Interpretation (TI) originator John G. Cramer, which derives the Born Rule (quantum probability rule) for radiative processes (emission and absorption) in a simple and transparent way, based on the Wheeler-Feynman-Davies'absorber' theory of radiation. It also shows that absorption is indeed perfectly well-defined in TI (contrary to skeptical claims … Continue reading Paper with John Cramer on Absorption in TI