Word: matter
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Dates: during 1980-1989
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...such a landmark announcement. In rival statements -- one from the Stanford Linear Accelerator Center in California, the other from the European Organization for Nuclear Research (CERN) in Geneva -- scientists disclosed findings they say establishes beyond a reasonable doubt that the universe contains precisely three fundamental types, or families, of matter. No more, no less...
...they are not animal, vegetable and mineral. In fact, all the matter most people are familiar with can be subsumed within one family of particles. This family includes the common electron, which hovers around the nucleus of the atom; the "up" and "down" varieties of quarks, now known to be the constituents of protons and neutrons; and an obscure particle known as the electron neutrino. Neutrinos have no charge and no measured mass, yet are thought to be among the most abundant particles in the universe...
These odds were calculated by observing the behavior of the Z particle, the heaviest known unit of matter. Zs are produced in the collision of smaller particles that have been accelerated to nearly the speed of light. By creating large numbers of Z particles, physicists were able to establish the energy range required to form a Z. Working backward from that energy range, they then calculated whether the laws of nature could accommodate more than the three known types of matter. Last week's results made it more than likely that the answer...
...this important? Because gnawing uncertainty about the number of particle families had plagued two theories that are the foundation of modern physics: the Big Bang theory of the creation of the universe and the Standard Model of the building blocks of matter...
Michael's Pub is packed. The green-and-white-checked tablecloths are jammed so close together that the waiters can hardly squeeze between, and patrons find themselves knocking knees with their dinner companions. No matter. They have come from around the world -- Japan, Italy, France, Scandinavia, South America -- to savor this moment. The random babel of a hundred conversations suddenly turns into an excited murmur as a sandy-haired man in an open-necked white shirt and corduroy trousers saunters in and heads for an empty table. He nonchalantly opens a tattered case and removes, then hooks together, the sections...