Edward Green wrote:
Uncle Al wrote:
Edward Green wrote:
Some characterisitic language used in the description of symmetries
existing or lacking in physical law seems to be rather misleading.
The symmetries are said to be "conserved", but the conservation of a
physical quantity is not implied; there is no conserved physical
quantity called "parity".
Oh yes there is! Your ignorance does not influence reality's
content.
http://physics.nist.gov/GenInt/Parity/cover.html
"Between Christmas of 1956 and New Year's Day, the first exciting
results emerged from a difficult but fundamental scientific experiment
at the National Bureau of Standards (NBS) in Washington, DC [currently
the National Institute of Standards and Technology (NIST)]. The
experiment showed, strikingly and convincingly, that in at least one
fundamental physical process, our world is distinguishable from its
mirror image."
Thus far I have no quarrel.
"Physicists had long assumed the opposite. They constructed their
theories so as to ensure that the corresponding mathematical property,
called parity, remains unaltered - is conserved - in all subatomic
processes. Thus this experiment brought about the fall of parity from
its exalted position alongside such well conserved physical quantities
as energy, momentum, and electric charge."
Well then, Al, either this is simply another example of poor language,
or I am indeed mistaken. I have no doubt many professionals _say_
"parity is conserved" or "parity is not conserved", but I think they
speak this way out of habit rather than reflection.
Ignorant idiot.
[snip]
Charge reversal, time reversal and parity reversal are not continuous
transformations, and as far as I know no conserved quantities attach to
discrete symmetries through Noether's theorem.
You are light on math and empty of known content.
I know just enough to be dangerous. ;-)
You harbor unbounded delusions of competence.
[snip]
Inversion of
all coordinates is a discrete process that cannot be approximated by a
Taylor series. Parity the symmetry is linked to parity the property
by other strong correspondences. Parity is conserved by strong
interactions but commonly violated by weak interactions (including the
Weak Interaction). As gravitation is the weakest known force, one
might optimistically expect a metric (parity-conserving) vs. affine
(parity-violating) gravitation anomaly.
As usual, you have loaded your canon with every bit of scrap you found
lying on the field, and some of it I do not recognize nor can I answer.
It is an old technique. Nonetheless, I have the conviction of a
simple conceptual clarity: A physical law is invariant with respect to
a certain symmetry if the corresponding change of variables leaves the
form of the law unchanged. Now, it might be that every physicist in
the world speaks of a physical law or interaction having this property
with respect to coordinate reflection as "conserving parity", but I
would respectfully point out, sir or ma'am, that I honor the weight of
culture, but your habitual language is inexact.
Empirical demonstration of parity nonconservation in January 1957
http://physics.nist.gov/GenInt/Parity/cover.html
made Tsung Dao Lee and Chen Ning Yang Noble Laureates/Physics in
December 1957. The speed record still stands. The first test of
gravitational parity violation will be complete in mid-September. The
whole of physics is looking for Lorentz violation,
http://www.physics.indiana.edu/~kostelec/faq.html
Uncle Al simply got there first - unburdened by PERT charts, budget,
staff, management, equipment, progress reports... or expectations of
productivity. He called out to the Severely Gifted and they
volunteered an Army of Light. If it succeeds at the end, so much the
better.
--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz.pdf