Dear Dr. Dolby,

I'm reading your latest gr-qc/0406034, "The Conditional Probability Interpretation of the Hamiltonian Constraint",

http://xxx.lanl.gov/abs/gr-qc/0406034

You quoted Karel Kuchar's criticism to Don Page (gr-qc/0406034, p. 10):

"You always apply the conditional probability formula to calculate the conditional probability of a projector at a single instant of an internal clock time. You never apply it to answering the fundamental DYNAMICAL question of the internal Schrödinger interpretation, namely "If one finds the particle at Q' at the time T', what is the probability of finding it at Q'' at the time T''?". By your formula, that conditional probability differs from zero only if T' = T'' and Q' = Q''. In short, your interpretation prohibits the time to flow and the system to move!"

The response from Don Page: "In my viewpoint, only quantities at a single instant of time are directly accessible, and so one cannot directly test the two-time probability you discuss."

Then you added: "We do not intend to defend this response here. It is the opinion of the author that, if Kuchar's claim were correct, it would indeed amount to a reduction ad absurdum of the CPI."

It seems to me that refuting Kuchar's claim is a daunting task,

http://God-does-not-play-dice.net/Pullin.html#7

Perhaps you would need to solve the Hilbert space problem,

http://God-does-not-play-dice.net/Kuchar.html

then eliminate the "mysterious time" of Bill Unruh,

http://God-does-not-play-dice.net/Pullin.html#Unruh
http://God-does-not-play-dice.net/Unruh.html

and finally suggest some "relational" interpretation,

http://God-does-not-play-dice.net/Pullin.html#relationally

I wonder if you or some of your colleagues can make it.

Regards,

D. Chakalov
--
http://God-does-not-play-dice.net
 
 

Note: If Carl Dolby replies and says something interesting, I won't report it here but will switch to private mode. There is a lot more to be said about Karel Kuchar's criticism and the "mysterious time" of Bill Unruh. They have set the record straight many years ago, but some people still cannot grasp the reasons why Bill Unruh introduced his so-called mysterious time (B. Unruh, No time and quantum gravity, in: Gravitation: A Banff Summer Institute, ed. by Robert B. Mann and Paul Wesson, World Scientific, Singapore, 1991, pp. 260-275).

This mysterious time must exist, and the hidden 'unmoved mover' (Karel Kuchar) must exist, but they are still missing in our mathematical presentation of the nature of time. Bill Unruh and Karel Kuchar have explained the problems with math. Rigorously. Besides, there is no way we can possibly avoid 'the only truly isolated system'. I will be happy to elaborate, from textbooks (cf. Chris Isham's Lectures on Quantum Theory). Surely Mother Nature is not living in one instant only, having "quantities at a single instant of time" (Don Page) to be "directly accessible" for calculations. A "single instant of time" -- with respect to what? To that same "single instant of time" maybe? That's how you begin to define probabilities "relationally". Only they don't sum up to unity, sources say. So, you need the two-time probability of Kuchar and the "mysterious time" of Unruh.

Moreover, everyone can test this so-called mysterious time with her/his brain (more on GR, QM measurements, and the human brain here). The problem has been identified by Tito Levi-Civita in 1917, fifty years prior to the discovery of Wheeler-DeWitt equation: the total energy-momentum of a closed system would always be equal to zero. It goes without saying that Einstein was fully aware of this ultimate problem.

See also Hermann Weyl, and the question posed by Richard Feynman below. It may sound like a joke, but it isn't. If we can cancel the gravitational field on paper, as explained by Hermann Weyl in 1922, then we're in the same murky waters as with QM, as stressed by Erwin Schrödinger in 1935: "The rejection of realism has logical consequences. In general, a variable has no definite value before I measure it; then measuring it does not mean ascertaining the value that it has. But then what does it mean?" No answer. Just 'shut up and calculate'.

This isn't the first time I'm trying to contact Carl E. Dolby. He hasn't yet replied to my first email of Fri, 06 Jun 2003 15:19:29 +0300, and then all my email send to his two email addresses was bounced back. I guess I'm talking to a brick wall. Clifford Will, for example, was far more polite, he simply asked me not to send him email. That's probably more difficult than bouncing an email, but works perfectly well. Who cares about Einstein's legacy and quantum gravity?

Just keep quiet and have fun. Shut up and calculate, and delete all email that could make you think. Carl Dolby, Clifford Will, and many more people have set the standards with handling unsolicited email. Other have stated bluntly that "you do not know enough theoretical physics to help with any research in that area."

So be it.

D. Chakalov
June 11, 2004
Last update: June 15, 2004
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Is it not possible that perhaps gravitation is due simply to the fact that we do not have the right coordinate system?

Richard Feynman, Lectures on Physics