Why Everettians Should Appreciate the Transactional Interpretation

TL;DR

The paper argues that the transactional interpretation of quantum mechanics offers a conceptually clearer and more realist alternative to the Everett interpretation, avoiding many conceptual difficulties associated with observer-centric views.

Contribution

It demonstrates that TI, especially in its possibilist form, aligns with realist principles and simplifies understanding quantum phenomena without invoking observers or consciousness.

Findings

TI does not require observers or consciousness.

PTI treats state branches as real dynamical entities.

Born probability emerges naturally in TI.

Abstract

The attractive feature of the Everett approach is its admirable spirit of approaching the quantum puzzle with a Zen-like "beginner's mind" in order to try to envision what the pure formalism might be saying about quantum reality, even if that journey leads to a strange place. It is argued that the transactional interpretation of quantum mechanics (TI), appropriately interpreted, shares the same motivation and achieves much more, with far fewer conceptual perplexities, by taking into account heretofore overlooked features of the quantum formalism itself (i.e. advanced states). In particular, TI does not need to talk about brain states, consciousness, or observers (rational or otherwise). In its possibilist variant ("PTI"), it shares the realist virtues of treating state vector branches as genuine dynamical entities, without having to explain how or why all of their associated outcomes actually happen (they don't), how to account for a plenitude of counterpart observers in some coherent notion of trans-temporal identity of the bifurcating observers (observers don't bifurcate in TI), nor how the certainty of all outcomes could be consistent with any coherent theory of probability, let alone the Born probability (the Born probability emerges naturally in TI). In short, TI is precisely the one-world interpretation Kent is looking for in his (2010).