Are you making this up as you go along? Neutrons are not made of protons. They are both baryons, composed of gluons and quarks.
The oscillating neutrino theory is an attempt to salvage physics. New physics are required to understand neutrinos, IMO, supersymmetry will provide the answers.
PARTICLE PHYSICS:
CERN Collider Glimpses Supersymmetry--Maybe
Charles Seife
It's a notion worthy of The X-Files: a shadowy world of doppelgangers, existing in eerie counterpoint to the one we know. Last week, particle physicists at the CERN laboratory in Switzerland announced that they may have caught the first glimpse of that world. By smashing together matter and antimatter in four experiments, they detected an unexpected effect in the sprays of particles that ensued. The anomaly is subtle, and physicists caution that it might still be a statistical fluke. If confirmed, however, it could mark the long-sought discovery of a whole zoo of new particles--and the end of a long-standing model of particle physics.
Other scientists are intrigued by the findings. "Often with an anomalous result, after a few hours' work, you say, 'This can't be right,' but here this is not the case," says Gordon Kane, a physicist at the University of Michigan, Ann Arbor. But they are also skeptical. "After having been bitten 15 times, I'm twice shy," jokes CERN physicist John Ellis. "I think it's probably going to turn out to be some background fluctuation, unfortunately."
The finding threatens the slightly creaky Standard Model of particle physics, which provides a mathematical framework that binds together all of the fundamental particles (quarks, neutrinos, electrons, taus, muons, gluons, and so forth). And it supports a newer, fancier model known as supersymmetry. By linking the particles that make up matter (fermions) with those that carry forces (bosons), supersymmetry unifies all the quantum forces at very high energies. In the process, it also doubles the roster of particles. Each fermion, such as a quark, neutrino, electron, or tau, has a bosonic twin: an s-quark, neutralino, s-electron, or s-tau. Likewise, every boson has a fermionic twin: The photon has the photino, and each gluon has a gluino.
The CERN scientists put the models to the test at the Large Electron-Positron Collider (LEP), a 27-kilometer magnetic ring near Geneva where physicists had long been smashing electrons and antielectrons together, creating showers of subatomic debris. They were particularly interested in showers containing pairs of tau particles. Like electrons, muons, and quarks, tau particles are thought to be fundamental particles--indivisible chunks of matter. The Standard Model allows several different chains of particle interactions, known as channels, by which a colliding electron and antielectron can produce a pair of tau particles. Supersymmetry allows not only all of those channels, but also others that involve the twin particles unknown in the Standard Model. Each theory also predicts how many tau particles ought to result from collisions at different energies--but the answers aren't always the same.
Those differences were the test. At low energies, the number of tau particles LEP produced matched calculations based on the Standard Model. But in 1998, when engineers at CERN pushed the energies of the collisions above 189 billion electron volts, things began to change. "Over the last couple of years, there has been a slight excess," says CERN physicist Gerardo Ganis. Instead of observing about 170 tau pairs of a certain type, as the Standard Model predicts, physicists have seen 228--a figure consistent with supersymmetry.
Barring some unknown type of systematic error that affects each of the four experiments, each experiment has roughly a 5% probability of seeing the excess because of a chance statistical fluctuation, Ganis says. "But when put together, it's a fraction of a percent." That's still too high for physicists to break open the champagne (to declare a bona fide detection, they would need to push the probability of error below 0.001%), but it is enough to raise eyebrows.
If real, the tau-pair excess would signal the end of the Standard Model and the beginning of the supersymmetric era. However, the result may also be a fluke that will disappear with more data, as other supersymmetry sightings have done in the past. More data are due to be released on July 20, and the experiments will continue until September. That probably won't be enough time to resolve the issue, the physicists say.
Ironically, if the death knell for the Standard Model comes, it probably won't toll at LEP: This fall, the device is slated to be dismantled to make way for the Large Hadron Collider experiment.
Volume 289, Number 5477, Issue of 14 Jul 2000, pp. 227-228.
Copyright © 2000 by The American Association for the Advancement of Science. |
