|Subject: A Quantum Theory of Events
Date: Thu, 23 Jan 2003 09:44:09 +0200
From: Dimi Chakalov <email@example.com>
CC: firstname.lastname@example.org, email@example.com,
firstname.lastname@example.org, email@example.com, firstname.lastname@example.org
Dear Dr. Boström,
In your recent quant-ph/0301049, you wrote: "Also, it is a great challenge to find a relativistic formulation of QET."
Perhaps this is impossible in principle. If you need to introduce some non-unitary dynamics in STR to find a relativistic formulation of QET or a relativistic quantum theory of measurement, I think the task will be impossible,
Alternatively, if you choose to stick to the unitary requirement and hence be confined into the so-called consistent/confined histories a la Hartle, etc., you run into all sorts of ambiguities due to the interference. It seems to me that some recent efforts along the lines of decoherent histories approach (see 'the non-uniqueness of the retrodicted past' in J.J. Halliwell, quant-ph/0301117 and quant-ph/0101099) have ignored this well-known problem,
Anyway, I will be happy to learn what precisely are the challenges to find a relativistic formulation of QET.
With kind regards,
John S. Bell
Note: The challenges to find a relativistic formulation of QET are exhibited in the recent "Basic Concepts of a Quantum Event Theory", quant-ph/0411175 v1. Here Kim J. Boström wrote:
"The Quantum Field Theory leads to astonishingly precise predictions and satisfies both quantum mechanical and relativistic demands, although there still appear certain annoying infinities that have to be removed by hand from the calculations. Under certain circumstances, and in particular when trying to incorporate the gravitational aspect of Relativity, those infinities can no longer be removed, and it remains an unsolved riddle how a unified theory should tackle with this problem."
Perhaps this isn't surprising, since Postulate 1 (Particle events) reads: "The history of the universe is composed out of particle events." These 'events' are specified in the following manner:
"Let us denote the so-defined concept of physical time the flowing time. In particular, the concept of flowing time implies that there are no "holes" within the evolution of a system. In other words: A physical system is at any point in time in a particular state."