Natural Science Forum / Physics / Research / June 2005

Can anyone recomment a good book on the Arrow of Time? Ideally not too
technical ie not too many equations.
Specifically including treatments of QM measurement, the perception of
the 'flow' of time, the expansion of the universe and some information

Does anybody have more details about the argument developed in
Weinberg, v II p 381-382 (around formula 22.3.39) where it is argued
that "the anomalies in a given set of symmetries therefore are
unaffected by the possible presence of fermions with a mass allowed by

I was wondering the following according Dimension Analysis. If you have
found the dimensionless groups (DG) from Buckingham PI theorema, then
consequently the relationship between the different groups should be
found from observations. I wonder whether it is forbidden to raise a

  Several months ago, Frank Wilczek wrote two
articles about F=ma (appearing in "Physics Today"
Oct and Dec, 2004). He thinks it's a culture to
accept such a formula. It seems to me he tried to

Does anyone know of any quantitative explorations of the Standard Model
at finite temperatures? I am looking for literature regarding the
thermal distributions of W+, W-, Z and photons (the force carriers of
the Electroweak group).

It is well known that QM gives a wave structure of the probability
density for the presence of a quantum oscillator in a box. Has anyone
checked this?
I mean has anyone made a straightforward experiment  to check if there

John Baez   Oct 22 1999, 3:00 am
Subject: Re: chronons?
<snip>

Dear Sir,
When I find the site
'http://www.cup.cam.ac.uk/onlinepubs/412714/412714top.html' online I
couldn't find it. That site is concerning x-ray crystallography from

I've got a little problem in trying to understand the constraints. In
particular I'm stumped as to how one can show that the momentum
constraint is a conserved quantity. I'm working from MTW, where the
momentum constraint is written as

Can someone out there point me to some good experimental data for the proton
and neutron mass radii.  I have found it very difficult to find such data
anywhere.
If possible, this should be apples-to-apples data, i.e., from using

In recent threads in sci.electronics.design, rec.crafts.metalworking,
and sci.physics, I have written about my attempt to convert Burden's
Surplus Center #10-1134 motor into a pedal powered self-excited
induction generator (SEIG). The consensus is it won't work, and I am

If we consider a uniform Newtonian self-gravitating gas (assume for
simplicity that the density of particles is initially uniform, and that
the particles are pointlke with mass m).
Then what is the diffusion constant/diffusion tensor describing the

                                                    Date:22-6-2005
Dear Sir,
How do we know that crystal is single and perfect? Why do we refine the
data after x-ray diffraction method? I hope your reply.

As I am unfamiliar with FT in crystallography I would like to know that
what facts give us from FT contour and surfaces, atoms positions and
other informations when we got FT and Difference Fourier map.
Zaw

I could need some help on the following question:
What is the structure of the homogeneous space SL(2,C)(x)R^4/SU(2)xR^4
? (x) is a semidirect product (Poincare-Group), but x is direct. Is the
h.s. isomorphic to the hyperboloid in three dimensions, as it would be