Hi Ken,

Do these interesting results imply that if one doesn’t want to admit retrocausality in quantum physics one must also deny time reversal symmetry? At what level must one give up time reversal symmetry? Must unitary time evolution or the Schroedinger equation be modified?

Thanks,

Lee

Dear Dieter,

Thank you for your remarks. I couldn’t disagree more, on substance as well as methodology. First, I don’t agree that the Everett interpretation is “inferred” rather than invented. Without an operational hypothesis as to how the mathematical symbols correspond to measured values a theory, any theory, is just empty mathematical…[Read more]

Dear Dieter,

I’m sorry, I misunderstood you; I thought by referring to the wavefunction, as an alternative to hidden variables, you were referring to dBB.

Everett Many Worlds fails to answer any of the questions that puzzle me about quantum physics. I can elaborate my objection to it but others such as David Albert have already done a…[Read more]

Dear Dieter,

I certainly do want to avoid many worlds. For reasons we explain in our new book with Mangabeira Unger, I don’t think that the present framework of quantum theory can apply to the universe as a whole.

I agree the wave function contains more than a probability distribution-its phase appears to be “ontic”. But I don’t like that…[Read more]

Dear Bob,

Many thanks for your comments. My first response is that I don’t think that the REF has the issue with retrodiction you mention, but I’ll look into it.

I haven’t thought through your consistent histories framework carefully in many years so I will take your invitation to do so again. At one time there was an argument by Dowker and…[Read more]

Dear Shan,

I agree with you strongly. But deciding that the wavefunction is ontic, while very important, is of course not the end of the discussion, it is the beginning. It opens up the floor for us to propose hypotheses as to what beables the wave function corresponds to. Quantum mechanics doesn’t tell us, because of the measurement p…[Read more]

Dear Shan,

Sure, as I wrote, the theory can be tested by doing exactly what you say: construct a multiparticle entangled state of many degrees of freedom that would be very improbable to have been created naturally. If nonetheless the Schroedinger equation is satisfied that is evidence against the real ensemble formulation. Or you could try to…[Read more]

Dear Ken,
Thanks so much for your response. Again, I’llgo point by point:

“After reading through some of the PIRSA slides, I think I see the big-picture of what you’re attempting here… and I certainly appreciate that having Hamilton’s Principal Function as the phase of the wavefunction might invoke an interpretation where the distant past is d…[Read more]

Dear Bob,

Thanks enormously for your interest. Let me answer your questions in sequence:

“Can you say a bit more about what is driving your ideas? Obviously there is
some discontent with quantum mechanics as currently formulated, but what is it
that you think you can improve on?”

I am driven by the now more than 40 year failure to go beyond…[Read more]

Dear Shan,

Thanks for your interest and question. You raise an important issue which is the definition of the ensembles corresponding to the quantum state. These are defined to consist of similarly prepared systems with similar external environments and the same constituents. The crucial issue, which I do address in section 6 of the paper as…[Read more]

I am having difficulty uploading the pdf of the talk, but interested participants can download the pdf of a similar talk from http://pirsa.org/13050072/

The file of the talk is attached here: