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Thanks for sending the slides, Avshalom. It was difficult to see exactly what they mean in the absence of your corresponding presentation, so my questions and comments may miss the point. I appreciate your willingness to engage on this issue.
The slides you point to (9-10) indicate a “revision of history,” akin to Cramer’s TI “pseudo-time” process for forming a transaction. The questions in my response to Cramer’s 2015 paper (posted in a Reply to your paper) are therefore relevant. Specifically, where is the “pseudo-time” process taking place? Certainly not in spacetime or we wouldn’t be talking about “pseudo-time.”
I ask again, Why is there any “sequence of stages” in “pseudo-time” at all? Any wave coming from a future absorber (in TI or TSVF) knows whether or not it received the emitted photon. So, why are all the possible absorbers sending advanced waves into the past to the Source emission? Why not have the actual absorber of the received photon send an advanced wave back in time to the Source? Then, the Source knows exactly what to emit, because it knows how the particles will be measured and better yet, it knows what the outcome will be!
It seems to me that Ruth Kastner’s Possibilist TI has an answer for these questions, yet Cramer dismisses PTI as “unnecessarily abstract” while not providing an alternative. Do you have an alternative? Have you considered PTI? If not, why not?
Thanks again for the discussion 🙂
P.S. I’m biased towards PTI because it strikes me as the “perspectival” (Price’s term) counterpart to RBW. That is, I believe you can choose to do physics in either the 4D view or the time-evolved, embedded “perspectival view” of the Block Universe. In the 4D view, there is no need for “time-evolved” or “retro-time-evolved” explanation if you rather provide a “global constraint” as in Price’s Helsinki (toy) model or the adynamical global constraint of RBW. See for example, the Geroch quote and paragraph thereafter on p 136 of https://ijqf.org/wp-content/uploads/2015/06/IJQF2015v1n3p2.pdf. If you don’t want to lose a preferred present moment (Now), then you must somehow incorporate the subjective uncertainty of the future. A “pseudo-time” is not necessary for doing this, since relativity admits spacetime foliation via proper time on a family of geodesics (in all spacetimes of known relevance anyway). That’s what PTI does. As I point out in my recent General Block Universe Discussion post http://www.ijqf.org/forums/topic/general-block-universe-discussion, there is a compromise associated with either view. The 4D view loses completeness with its necessary omission of Now, while the perspectival view loses coherence per relativity of simultaneity, i.e., you need a preferred frame for the globalization of Now from individual worldlines. In my opinion, the 4D and perspectival views are complementary views of one and the same reality a la the figure-ground illusion, neither contradicts or refutes the other.