🚀 go-pugleaf

On Apr 1, 9:12 am, OsherD <mdocto...@ca.rr.com> wrote in sci.physics:
> From Osher Doctorow
>
> D. H. Hsu and David Reeb of the University of Oregon USA, in
> "Unitarity and the Hilbert space of quantum gravity," 6 pages, arXiv:
> 0803.4212 v1 [hep-th] 28 Mar 2008, certainly did not plan to
> "demolish" Quantum Gravity, and indeed suggest way of explaining their
> results via extra principles, but in fact their paper appears to
> demolish Quantum Gravity in the following sense.
>
> Under assumptions:
>
> 1) Physics is unitary,
>
> and
>
> 2) Black hole evaporation is complete (no topological change, no
> remnants),
>
> then almost the whole volume of semiclassical phase space would not
> correspond to allowed states in a Quantum theory of Gravity.  It
> should be noted that the above volume corresponds to highest entropy
> configurations.
>
> "Unitarity" Principle means that knowledge about the state of a system
> at one time or instant is equivalent to the same at any other time or
> instant, and seems to allow prediction of the future.  This seems to
> be obtained from evolution equations between states at two different
> times.
>
> One of the difficulties with Quantum Theory appears to go back to
> Entropy, while another goes back to Hilbert Space.  I should remind
> Readers, by the way, that black hole evaporation has been basically
> the result of Stephen Hawking, whose thermodynamic-Entropy methods are
> well known, so that if something is wrong with Entropy for example,
> Hsu and Reeb's results may lead to further (unrestricted?)
> "demolitions".

Some day Einstein zombie world (in the present context "Clausius
zombie world" would be more appropriate) will realize in horror that
everything is wrong with Entropy:

http://philsci-archive.pitt.edu/archive/00000313/
Jos Uffink: "The historian of science and mathematician Truesdell made
a detailed study of the historical development of thermodynamics in
the period 1822-1854. He characterises the theory, even in its present
state, as 'a dismal swamp of obscurity' (1980, p. 6) and 'a prime
example to show that physicists are not exempt from the madness of
crowds' (ibid. p. 8)...Clausius' verbal statement of the second law
makes no sense...All that remains is a Mosaic prohibition; a century
of philosophers and journalists have acclaimed this commandment; a
century of mathematicians have shuddered and averted their eyes from
the unclean...Seven times in the past thirty years have I tried to
follow the argument Clausius offers... and seven times has it blanked
and gravelled me... I cannot explain what I cannot understand....This
summary leads to the question whether it is fruitful to see
irreversibility or time-asymmetry as the essence of the second law. Is
it not more straightforward, in view of the unargued statements of
Kelvin, the bold claims of Clausius and the strained attempts of
Planck, to give up this idea? I believe that Ehrenfest-Afanassjewa was
right in her verdict that the discussion about the arrow of time as
expressed in the second law of the thermodynamics is actually a RED
HERRING."

Pentcho Valev
pvalev@yahoo.com