A Unified Account of Relativistic and Non-Relativistic Quantum Theory

The non-technical presentation of this material is available in my new book for the general reader, available here and as a Kindle version here. The Possibilist Transactional Interpretation: A Unified Account of Relativistic and Non-Relativistic Quantum Theory that Solves the Problem of Measurement Ruth E. Kastner 17 February 2015 1 Introduction The transactional interpretation of … Continue reading A Unified Account of Relativistic and Non-Relativistic Quantum Theory →

Free Will Part II: No need to be disillusioned

Last week I argued that agents making free choices do not in fact have to violate any physical law, in view of quantum indeterminism. Rather than being a ‘slave’ to the quantum statistics, as some philosophers have argued (e.g. Ted Sider, 2005), a choosing agent can be governed by quantum propensities while still having enough … Continue reading Free Will Part II: No need to be disillusioned →

Reply to Physics Today article and arxiv.org post re ‘Quantum Darwinism’

Comment on “Quantum Darwinism, Decoherence, and the Randomness of Quantum Jumps,” arxiv:1412.5206 R. E. Kastner University of Maryland, College Park December 18, 2014 This brief note points out an extant rebuttal in the literature to the claims made in a recent publication by Zurek [1]. In [1], it is stated that “Decoherence selects preferred pointer … Continue reading Reply to Physics Today article and arxiv.org post re ‘Quantum Darwinism’ →

Brian Hepburn reviews my book on PTI in the Canadian journal _Dialogue_

"In this book Ruth Kastner describes and defends a mature form of the transactional interpretation (TI) of quantum mechanics, an interpretation first put forward by John Cramer in the 1980s. Most of the 9 chapters and 3 appendices are suitable primarily for a popular audience (“accessible to the interested layperson with a mathematics and / … Continue reading Brian Hepburn reviews my book on PTI in the Canadian journal _Dialogue_ →

Why the World Cannot Really Split in the Many-Worlds Interpretation

In the Many Worlds interpretation, the universal quantum state is a giant superposition of all objects in the universe: There is no ‘wave function’ collapse in this interpretation, so everything remains entangled. How then does this universe ‘split’? The usual story says that a measurement process yields several possibilities, much like the different possible sizes … Continue reading Why the World Cannot Really Split in the Many-Worlds Interpretation →

Decoherence and ‘Quantum Darwinism’: not a cure for Schrodinger’s Cat.

It is widely thought that decoherence solves the measurement problem in a Many Worlds approach to quantum theory. In fact, this is claimed to be settled science in many internet sites with information on quantum theory. But this is not correct. Those 'Quantum Darwinism' arguments depend on smuggling in a hidden premise that is inconsistent … Continue reading Decoherence and ‘Quantum Darwinism’: not a cure for Schrodinger’s Cat. →

Why quantum theory isn’t a shell game (PBR Theorem for the layperson)

The following is an excerpt from an Appendix of my forthcoming book, Understanding Our Unseen Reality: Resolving Quantum Riddles (Imperial College Press). In the book, quantum states (‘kets’) are represented by triangles. The proof of Pusey, Barrett and Rudolph demonstrates that quantum states cannot be taken as approximate descriptions of underlying, hidden properties. To present … Continue reading Why quantum theory isn’t a shell game (PBR Theorem for the layperson) →