Download da una versione vecchia (2004) del libro complexity

DA UNA VERSIONE VECCHIA (2004) DEL LIBRO COMPLEXITY
A few examples I have been involved in are reported in Figure.
MY CONTRIBUTIONS
 Strangeness a new quantum number to be additively conserved
for the same particles (mesons): not as it was believed to be
+1 for mesons (θ0 , θ+ )
and

1 for baryon (⋀0 ).
Needed the direct experimental observation of meson production
in a pair of neutral mesons (θ0 + θ̅0 ) & of a pair (θ+ + θ̅0 ) .
Exactly what was discovered by (A.Z.) when he came in the
Blackett group. The discovery was in 1956, published January
1957 [1].
 The 3rd lepton, HL (now called ) with its own neutrino, HL
(now called ),
despite the abundance of neutrinos: e and .
 Antimatter
despite S-matrix and C, P, CP, T breakings.
 Nucleon Time-like EM structure
despite S-matrix
 No quarks in violent (pp) collisions
despite scaling.
 Meson mixings
V  PS : (51º)  (10º)  0 despite SU(3)uds .
 Effective energy: the Gribov QCD-light
despite QCD-confinement.
 The EGM effect and the running of 1 2 3 versus energy with
the convergence at E1 2 3.
 The GAP between E1 2 3 and ESU .
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Point 1. To propose the existence of a third lepton was considered an
“unnecessary” complication. A theoretical leader at CERN was saying in fact: why
should nature be so complicated to have another neutrino when it can do all that is
needed with just one”. When the third lepton, HL, was proposed and the technology
was developed to search for its existence, the second neutrino had not been
discovered.
Point 2. The existence of antimatter was proposed by Dirac in the 1930s
when Dirac and Weyl had discovered the symmetry operator C, which describes the
invariance of all physical phenomena when all charges are reversed. By 1964, all
symmetry operators were discovered to be not valid in the real world, therefore the
existence of antiparticles could not guarantee the existence of antimatter since no one
knew how to describe the nuclear forces using the mathematics of the Relativistic
Quantum Field Theory (RQFT). In fact, the 1960’s were the period of triumph of the
so-called S-matrix theory, which was the negation of RQFT. The simplicity of
Nature could have been along the line of allowing the antimatter not to exist. In fact,
at the Planck scale the RQFT loses its foundations [16] and only an effective theory
can “predict” the existence of antimatter. The present status is that the existence of
antimatter is on firm experimental grounds even if firm theoretical predictions are
missing.
Point 3. If S-matrix is enough to explain the simplicity of Nature, why should
we complicate the picture with the Time-like electromagnetic structure of a simple
particle like the proton? According to the dominant theoretical structure of the
1960’s this structure should not be there. The experimental results have proved its
existence, despite S-matrix. The present understanding involves the Instantons (inst).
Point 4. According to experimental results in high energy scattering, the
proton appeared to be composed of “pieces” (called “partons” by Feynman) whose
interactions become very weak at increasing energies. This was the meaning of the
experimental effect discovered at SLAC and called “scaling”. Platonic simplicity
would suggest that a proton should break into its constituent “partons” if we collide a
pair of protons at very high energy. No pieces, be they “partons” or “quarks”, were
found at CERN in very precise and extreme high energy collisions of protons. Why
this further “complication”? The answer is in the forces (QCD) acting between
proton “pieces”: quarks and gluons. These forces (QCD) are non-Abelian, in
contrast with the electromagnetic forces described by QED. The non-Abelian nature
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implies that the strength of a force, acting inside a proton between its “pieces”,
increases with distance. When this distance is of the order of one Fermi (10 13 cm),
the attraction between quarks and gluons becomes very large and the proton cannot
break up. No one had been able to think of non-Abelian forces before we were faced
with the experimental complication of explaining why a particle with structure (the
proton) cannot break up into its constituents. If the world was simple, all forces
should be like QED, Abelian. In this platonic, simple world, we could not exist,
because the protons will easily break into pieces.
Point 5. Two examples of nuclear “glue” are the vector and the pseudoscalar
mesons. Simplicity would require no “mixing” in these mesonic states. If “mixing”
needs to be there, simplicity would imply that the two mixing “angles” (the “angle” is
a parameter which measures the mixing) be equal. V = PS. The experimental
results establish that they are different. Once again these effects are understood as
due to Instantons.
Point 6. The effective energy – as said, is theoretically not understood – and
its discovery was related to what Gribov defined as the “hidden side of QCD”. It is
the “Effective Energy” which produces what Gribov called “the QCD light”.
Point 7. Shows that during more than ten years (from 1979 to 1991), no one
had realized that the energy threshold for the existence of the Superworld was
strongly dependent on the “running” of the masses. This is now called: the EGM
effect (from the initials of Evolution of Gaugino Masses). To compute the energy
threshold using only the “running” of the gauge charges (1, 2, 3) corresponds to
neglecting nearly three orders of magnitude in the energy threshold for the discovery
of the first particle (the lightest) of the Superworld [11].
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