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The enigma
of the solar neutrino deficit.
...In
classical General Relativity one implicitly assumes
that the universe is composed of a single sheet. Nothing indicates, say
some, that it is necessary to envisage a different configuration.
Indeed.
The fusion reactions
at work in the heart of the sun produce energy
in the form of:
-
Photons
-
Neutrinos.
...Neutrinos
interact very little with matter, they therefore leave
the sun without difficulty. The energy in the form of photons travels
painfully toward the surface of the sun, the chromosphere, at the rate
of successive absorptions and re-emissions and thanks to
the convection that reigns in the star. When this energy reaches
the chromosphere it is emitted in the form of photons.
...On
Earth we therefore capture, modulo this delay, photons and neutrinos. Until
a fairly recent date one did not know how to measure this flux of neutrinos,
although every cubic centimeter of our person is crossed
each second, unless mistaken, by ten billion neutrinos.
...The
measurement of this flux revealed a troubling fact. We capture
only about half of the expected neutrinos. This is the solar neutrino
deficit, the deficit in solar neutrinos. One will absolutely have
to find an explanation one day for this phenomenon, otherwise
it is all our knowledge of the dynamics of the sun (and of the stars)
that collapses.
...In
my last book, published by Editions Albin Michel, entitled "we have lost
half of the universe", I had written in the first
part that we had a theoretical grasp of the functioning of the stars
considered satisfactory. But as things move,
in the following book I will have to include a chapter entitled:
We have lost half of the solar neutrinos.
...Some
theoretical physicists are dismayed, others delighted. Indeed
here is the first phenomenon that really catches
quantum mechanics out. We will have to put this
back to work.
One universe, or
two?
What are the
speculative ideas currently in circulation?
Two first
references:
R. Foot and R.R. Volkas Phys. Rev. D Vol. 52 n°11, 1° dec 1995
Z.G.Berezhiani and R.N. Mohapatra Phys. Rev. Vol. 52 n° 11 1 dec 1995.
...Foot
and Volkas think that the universe is composed of two "sectors", ours
and a "mirror sector", in mirror, enantiomorphic, that is
to say "P-symmetric". The energy released
by fusion would therefore bring into play at once "classical"
neutrinos and "mirrors neutrinos", neutrinos belonging to the second "sector"
(neutrinos of the three types: electronic, muonic and tauonic, and,
of course, their anti-particles). Sector, sheet, layer: synonymous
words.
...Our
universe is not symmetric. It is the seat of what is called
the violation of the parity principle. "Right"
reactions do not take place at the same rate as their mirror images.
Classical reference:
T.D.Lee and C.N.Yang Phys. Rev. 104, 254 (1956)
...Foot
and Volkas "symmetrize" the universe by supposing that it possesses
a double, the mirror universe, where this violation of the parity principle
would take place in the opposite direction. Along the way, we have constructed a model
where neutrinos would possess "little brothers", CPT-symmetric,
using group theory.
...See:
"J.P.Petit & P.Midy: Geometrization of antimatter through coadjoint
action of a group on its momentum space." 3: Twin group. [On site: Geometrical
Physics B, 1-3 ], 1998.
...There
exists another problem, which encourages considering two
universes instead of a single one, it is the absence of primordial antimatter
in our universe. Normally, in its most primitive state the universe
was constituted, to borrow Steven Weinberg's word, by
"all sorts of radiations". The photons gave birth to
particle-antiparticle pairs, which hastened to go and annihilate
a little further on (electrons and anti-electrons, for example,
endowed with opposite electric charges, attract each other). The primitive
universe (the tohu-bohu of the Hebrews) is therefore a very
turbulent mixture, where radiation is ceaselessly converted into matter-antimatter
and vice-versa. Then the expansion of the universe lowers the energy of
the photons, which are then no longer capable of supplying these pairs of brother
enemies. The universe then empties at a frantic rate.
After thirteen seconds, everything is played out. Question: why are we
here? Why was this annihilation not complete.
Answer: no answer.
...Hence
the few papers of Andrei Sakharov, who was the first to
suggest that two universes might have been created
at the same time, instead of a single one.
A.Sakharov: "CP violation
and baryonic asymmetry of the Universe". ZhETF Pis'ma 5: 32-35 (1967); Translation
JETP Lett. 5: 24-27 (1967)
A.Sakharov: "A multisheet Cosmological model" Preprint Institute of Applied
Mathematics, Moscow 1970
A.Sakharov: "Cosmological model of the Universe with a time vector inversion".
ZhETF 79: 689-693 (1980); translation in Sov. Phys. JETP 52: 349-351 (1980)
A.Sakharov: "Topological structure of elementary particles and CPT asymmetry"
in "Problems in theoretical physics", dedicated to the memory of I.E.Tamm,
Nauka, Moscow 1972, pp. 243-247
Detail: In these two universes, the arrows of time are opposite.
In certain of his publications, Andrei Sakharov evoked the
fact that these "twin universes" might also be enantiomorphic,
in mirror.
Other approach
: superstrings. These are suggestions formulated by Schwarz
(Caltech), Green (Queen Mary College) and the Nobel prize winner Abdus Salam (Director
of the International Centre for Theoretical Physics of Trieste, professor at the Imperial
College of London).
Starting point
: groups and the E8 x E8 model. Reference: "Superstrings,
a theory of everything?". PC.W.Davis & J.Brown, Cambridge University
Press 1988.
John Schwarz:
The second symmetry E8 refers to another species of matter, often called
shadow matter. The objects formed from this constituent
would be totally invisible to us.
Michael Green:
One of the predictions that emerges from these theories concerns
a new type of matter that we would not be able to observe
directly, but which would interact with ours by means of the forces
of gravitation, although these particles of shadow matter could act
on one another through the other forces.
Abdus Salam:
From the theory of superstrings emerges a sort of
universe that would be a double of ours, but which could communicate
with it only through the forces of gravitation. What is interesting
is that this universe would determine the way in which supersymmetry
would be broken in our own universe and could shed some
light on the particular values of the masses of the different
particles.
But for the moment it
does not go any further. Nor do superstrings, for that matter.
...That being so, how to represent two universes closely interwoven
one within the other and communicating only through gravitation?
One can imagine two pairs of players equipped with filtering
glasses, who would then be incapable of seeing the pieces of the other
team. On the other hand each could guess the presence of an opposing
piece, nearby, on a "soft checkerboard":
...The
piece of matter (part played on the black squares)
, does not see the queen belonging to the "phantom game", but
detects its presence from the curvature that it creates
on the checkerboard (gravitation). See below:
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