Open System for Geniuses - by Chronostalker

We continue with J. G. Cramer’s "An overview of the Transactional Interpretation". Second paragraph reads:

At the interpretational level, the nonlocality of the quantum mechanics formalism is a source of some difficulty for the Copenhagen interpretation. It is accommodated in the CI through Heisenberg’s “knowledge interpretation'’ of the quantum mechanical state vector as a mathematical description of the state of observer knowledge rather than as a description of the objective state of the physical system observed. For example, Heisenberg in a 1960 letter to Renninger wrote[3], “The act of recording, on the other hand, which leads to the reduction of the state, is not a physical, but rather, so to say, a mathematical process. With the sudden change of our knowledge also the mathematical presentation of our knowledge undergoes of course a sudden change.'’ The knowledge interpretation’s account of state vector collapse and nonlocality is internally consistent but is regarded by some (including the author) as subjective and intellectually unappealing. It is the source of much of the recent dissatisfaction with the Copenhagen interpretation.

Nonlocality - if there is any at all, is not the source of any difficulty. The difficulty lies somewhere else: in the fact that QM is incomplete. It if was complete, nobody would pay any attention to apparent difficulties with nonlocality. The "knowledge interpretation" is indeed a problem, as we are not told how to describe individual physical system in an objective way. Heisenberg did not know the answer, so he tried to make his failure into a failure of everybody. But the "knowledge interpretation is not internally consistent" at all. Because the "knowledge" itself is not a part of the theory. A theory that pretends to be generally valid but then blames the most important process (verification of the theory with experiments) on external concepts that are not part of the theory (change of "knowledge") is not internally consistent. It is being considered as "internally consistent" only due to wishful thinking and lack of courage of the physicists and philosophers. The dissatisfaction with the Copenhagen interpretation because of its "knowledge interpretation" is not "recent" at all. It is as old as quantum mechanics itself.

The author has proposed an alternative and more objective interpretation of the quantum mechanics formalism called the transactional interpretation (TI). It employs an explicitly nonsocial “transaction'’ model for quantum events. This model describes any quantum event as a “handshake'’ executed through an exchange of advanced and retarded waves and is based on time symmetric Lorentz-Dirac electrodynamics and on “absorber theory'’ originated by Wheeler and Feynman. In the absorber theory description any emission process makes advanced waves (schematically represented by the time dependence exp(i omega t)) on an equal basis with ordinary “retarded'’ waves (exp(-i omega t)). Both advanced and retarded waves are valid orthogonal solutions of the electromagnetic wave equation, but in conventional electrodynamics the advanced solutions are conventionally rejected as unphysical or acausal. Wheeler and Feynman used a more subtle boundary condition mechanism to eliminate the non-causal effects of the advanced solutions.

Here we meet the first undefined concept: "quantum event". What is a "quantum event?" How does it differ from an "ordinary event"? It is a always a good idea to define the concepts one is using - otherwise no one will be able to understand the author. Then we have the concept of "advanced and retarded waves", but we are not told what kind of waves they are supposed to be? Waves of what in what? If "waves" are at the foundations of QM, then we immediately have a problem. Because quantum mechanics works perfectly well in a two-dimensional Hilbert space, that is how the simplest spin system is being described. But then there is no place fro "waves" whatsoever. Is the author going to abandon 90% of quantum mechanics that deals with spin systems? "Both advanced and retarded waves are valid orthogonal solutions of the electromagnetic wave equation"??? This sentence does not have any meaning whatsoever. What are "orthogonal solutions?" Orthogonal to what? In which space they are orthogonal? What has electrodynamics to do with quantum mechanics? For instance with quantum gravity?

In the Wheeler-Feynman picture when the retarded wave is absorbed at some time in the future, a process is initiated by which canceling advanced waves from the absorbers erase all traces of advanced waves and their “advanced'’ effects, thereby preserving causality. An observer not privy to these inner mechanisms of nature would perceive only that a retarded wave had gone from the emitter to the absorber. The absorber theory description, unconventional though it is, leads to exactly the same observations as conventional electrodynamics. But it differs in that there has been a two-way exchange, a “handshake'’ across space-time which led to the transfer of energy from emitter to absorber.

Now, if we have a more complicated theory, that involves more processes, including mysterious "erasing all traces", but "leads to exactly the same observations" as the simpler theory - what’s the point of developing such a theory?

To be continued…