Thnx for the reply, Yehonatan. You don’t need to concern yourself with the details of our approach, as you noted it doesn’t bear directly on your specific motives. I just wanted you to be aware of the fact that your 4D global perspective has company 🙂

Hi Matt,

Thanks for your interesting comments, some of which I basically agree.

But I think you misunderstood my paper. The paper does not aim to show the (realist) psi-epistemic view cannot solve the measurement problem. Rather, it only shows that the psi-epistemic view does not provide a straightforward resolution or a dissolution of the…[Read more]

Shan,

We have had so many discussions about this now that I am beginning to think that you are being deliberately obtuse, and trying to court controversy where there ought to be none.

Let me first note that not all ontological models solve the measurement problem, psi-epistemic or not. Some do and some don’t. Since Bohmian mechanics can be fit…[Read more]

Yehonatan, I read your paper. Is it published someplace, so we can reference it? Your approach shares many of the values found in the Relational Blockworld. See http://www.ijqf.org/wps/wp-content/uploads/2015/06/IJQF2015v1n3p2.pdf.

Shan, there is no superdeterminism in retrocausality with global constraints. Superdeterminism entails a time-evolved story per the Newtonian schema (NS), i.e., invoking a physical mechanism that “causes” the experimentalist to make certain choices. In Wharton’s Lagrangian schema (LS), the explanation is spatiotemporally holistic, e.g., Fermat’s…[Read more]

Shan, Thanks for the post. Here are a few thoughts.

1. You catch-out the ontogical models view at a weak point. For what they call “psi-epistemic” has to do with possible overlap of ontic states in the preparation of distinct state functions. But that has nothing to do with explaining collapse on measurement. In the earlier literature, as in…[Read more]

Mark: concerning “realist psi-epistemic view”. There’s no problem with the basic idea, so long as “realist” clearly modifies “view”. But a different parsing might make it seem that “realist” modifies “psi”, which would imply exactly the opposite of psi-epistemic (psi-ontic). That’s all I was getting at… 🙂

Shan: I’m not sure what you mean by “essential randomness”, or whether that would be ‘good’ or ‘bad’. But you are correct to imply that if there is some ‘special observable’ A in the real system that is perfectly correlated with the measurement B that we utilize on that system, then this correlation needs to be explained causally.

One option is…[Read more]

Ken, why do you think “realist psi-epistemic view” is “an interesting choice of words”? The title of our last RBW paper in IJQF was “Relational blockworld: Providing a realist psi-epistemic account of quantum mechanics” which we wrote after extensive correspondence with you.

Thanks for this, Shan.

I’m worried you’re setting up a bit of a straw man version of psi-epistemic models (you call it the “realist psi-epistemic” view, an interesting choice of words). I’d be surprised if there were many (or any!) quantum foundations people who take such a view.

Specifically, you are ascribing the following logic to anyone…[Read more]

As Price & Wharton point out, once you consider QM to be giving 4D distributions in spacetime (Lagrangian schema), rather than time-evolved distributions in configuration space (Newtonian schema), mysteries like the MP are resolved trivially. This is a psi-epistemic view.

Hi Aurelien,

Nice post!

Regarding ontology of MWI, it appears that a preferred structure (partition into subsystems, including virtual subsystems) of the Universe is needed. Otherwise sufficiency of decoherence for defining “branches” and/or reality of “world branching” are at stake. More technically: there exist mutually irreducible,…[Read more]

This is an interesting solution. A version of it is discussed in section 4.4. of “Four Tails Problems for Dynamical Collapse Theories”. There it is discussed in the context of the matter-density interpretation of GRW (sometimes called “GRWm”). The “denser” brains are the ones with the experiences of measurement outcomes. Since high density is…[Read more]

Dear Shan dear all, I gave a kind of reply to Shan’s work concerning psycho physical parallelism in the topic ‘The End of the Many-Worlds? (or Could we save Everett’s interpretation)’

with best regards Aurélien

Dear Lev, don’t worry: my aim was only to recognize the influence that your view on MWI has on mine (your work on bohm with the ‘surrealistic’ bullet and the cat was very great as well). I will add a sentence that you dont share my view.
with best regards Aurélien

I thank Aurelien for citing my works, but his acknowledgement to me at the end of his paper is misleading. Although I tried to explain my views to him in a couple of e-mails, I failed. Reading his presentation of my views I could not recognize them at all. I disagree with everything I saw in Aurelien paper.
Lev Vaidman

OK, good. But I guess I’m inclined to stick to my guns here — the relative positions of the particles determine the measurement outcome. Suppose the first particle is the one whose spin is being measured, and the second particle marks the top of the detection screen. Then if the two particles end up close together, the incoming particle is…[Read more]