This is extremely good news in terms of my Cloud Cosmology.
conjecture: The electron is formed as the maximum Platonic solid consisting of approximately ( for now until simulation ) 620 neutral neutrino pairings.
This conjecture will appear spherical and more complex forms are ruled
out on the most important elemental particle by direct empirical evidence. This means that my linkage of the neutral
neutrino as the component element in the electron sets our scales correctly for
further work to a high degree of confidence.
It is always nice to set aside real concerns at an early stage.
We will not be quite so lucky with the neutron before we are finished.
Electron Appears Spherical, Squashing Hopes for New
Physics Theories
The most precise measurement yet of
the electron’s shape casts doubt on ideas such as supersymmetry that predict a
zoo of undetected particles in the universe
Scientists are
unanimous that their current theory of physics is incomplete. Yet every effort
to expose a deeper theory has so far disappointed. Now the most sensitive test
yet of the shape of an electron—a property that could expose underlying “new
physics”—has failed to find hints of anything novel. The finding rules out a
number of favored ideas for extending physics, including some versions of a
popular idea called supersymmetry.
The result came
from a search for the so-called electric
dipole moment in the electron. A familiar example
of a dipole is a bar magnet, which is shaped like a dumbbell with a north and a
south pole. Electrons are traditionally thought of as spherical, but if they
had dipole moments, they would be slightly squashed. “It’s a question of: Does
the electron look the same no matter which way you look at it?” explains
physicist Jony Hudson of Imperial College London. “The dipole moment is
physicists’ technical way to describe if it’s symmetric or not.”
The Standard
Model of particle physics, which describes all the known particles in the
universe, predicts a practically zero electric dipole moment for the electron.
Yet theories that include additional, yet-to-be-detected particles predict a
much larger dipole moment. Physicists have been searching for this dipole
moment for 50 years. Now a group called the ACME collaboration, led by David
DeMille of Yale University and John Doyle and Gerald Gabrielse of Harvard
University, has performed a test 10 times more sensitive than previous
experiments, and still found no signs of an electric dipole moment in the
electron. The electron appears to be spherical to within
0.00000000000000000000000000001 centimeter, according to ACME’s results, which
were posted on the
preprint site arXiv. “It’s a surprise,” says Ed Hinds,
also of Imperial College London, who worked with Hudson on the previous
best limit, set in 2011. “Why on Earth is it
still zero?”
The experiments
are probing the quantum nature of an electron. According to quantum mechanics,
all particles, including the electron, should give rise to a cloud of virtual
particles around them that continually sweep in and out of existence. If the
standard model is all there is, then these virtual particles would be everyday,
run-of-the-mill particles. But if more exotic particles are out there, they
should pop up in the virtual clouds around electrons, causing the clouds to be
asymmetric—in other words, causing an electric dipole moment.
To search for this asymmetry,
scientists spin electrons to test whether they are round or oblong. Whereas a
billiards ball will spin smoothly, an egg will wobble. The same goes for an
electron with an electric dipole moment. The ACME researchers looked at
electrons in thorium monoxide molecules, whose heavy mass and special
characteristics would make wobbling more conspicuous. “Their choice of molecule
is very clever,” says Hudson, whose experiment uses another molecule, called
terbium fluoride. “I’m sort of jealous—I wish I’d thought of that.” Previous
generations of experiments looked for the effect on single atoms, which turned
out to be much more difficult. The ACME scientists relied on careful
measurements with microwave spectroscopy to notice any wobbling, and labored to
keep their experiment free of magnetic fields or other contaminants that could
cause systematic errors. “It’s hard because there are a lot of things that can
mimic the effect, and the dipole moment is just so small,” says Ben Sauer,
another member of the Imperial College London team
The new result
deals a significant blow to many new physics theories, most notably
supersymmetry, a favored idea that suggests each known particle in the universe
has a supersymmetric twin particle that has yet to be discovered.
“Supersymmetry is so elegant and somehow feels so natural that many people were
starting to believe it was right,” Hinds says. But if they exist, all these
twin particles should arise as virtual phantoms in the cloud around electrons,
giving it a measurable electric dipole moment. The lack of one so far backs
supersymmetry into a pretty tight corner. “It’s getting close to the point
where it’s make
or break for supersymmetry,” Hudson says. Although some basic
models of the theory have been ruled out by the latest measurement, more
complex models predict a small electric dipole moment that could be hiding in
the range physicists have yet to search. “You can endlessly make models of
supersymmetry,” says Eugene Commins, an emeritus professor of physics at the
University of California, Berkeley, who led the last search for the
dipole moment in atoms. “A good theorist can invent a model
in half an hour, and it takes an experimentalist 20 years to kill it.”
Searching for supersymmetric
particles is one of the prime goals of the Large
Hadron Collider (LHC), the world’s largest particle
accelerator, which smashes protons together at near light speed in a tunnel
underneath Switzerland and France. The accelerator is big enough to probe
energies around a teraelectron-volt (TeV)—right at the energy range predicted
for supersymmetric particles. So far, it has seen signs of no new particles
except for the last missing piece of the Standard Model of particle physics,
the Higgs
boson. “If there’s new physics at the
energy range where LHC is probing, you would have expected that it would also
produce a dipole moment substantially bigger than the limit we now have,” Hinds
says. “Now that this new result is out, you’re certainly making it highly
unlikely that there’s anything going on at the TeV level.” Undeterred, however,
the electron experimentalists will continue competing to push the dipole limit
lower and lower, in hopes that a signal may yet be found, and physicists are
eagerly awaiting the results from LHC’s next run in 2014, when it turns back
after a hiatus at higher energies than ever before.
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