About 70 years ago, only a small number of "elementary particles”, thought to be the basic building blocks of matter, were known: the proton, the electron, and the photon as the quantum of radiation. All these particles are stable (the neutron is stable only in nuclear matter, the free neutron decays by beta decay: n→p+e−+\overline{\nu}). Owing to the availability of large accelerators, this picture of a few elementary particles has profoundly changed: today, the standard reference Review of Particle Properties lists more than 100 particles. The number is still growing as the energies and luminosities of accelerators are increased.
Walter GreinerRelated topics
availability basic building decay electron elementary few free growing known large matter nuclear number particle picture quantum radiation reference review small stable standard thought 100 today years beta neutron proton overline photonRelated quotes
Gravitational force is simple, and a thing by itself, as also are electric and magnetic forces as long as the electric and magnetic poles stand at rest. But as soon as motion comes into the picture, the whole situation is changed. Forces of new kinds come into play, for moving electric charges exert magnetic forces in addition to the electric forces they exert when at rest, while moving magnets exert electric forces in addition to the magnetic forces they exert while at rest. When the exact laws governing these intricate laws had been discovered by a great number of experimenters, Clerk Maxwell succeeded in expressing them in a mathematical form which was both simple and elegant.
James Jeans
If supersymmetry plays the role in physics that we suspect it does, then it is very likely to be discovered by the next generation of particle accelerators, either at Fermilab... or at CERN... Discovery of supersymmetry would be one of the real milestones in physics, made even more exciting by its close links to still more ambitious theoretical ideas. Indeed, supersymmetry is one of the basic requirements of "string theory," which is the framework in which theoretical physicists have had some success in unifying gravity with the rest of the elementary particle forces. Discovery of supersymmetry would would certainly give string theory an enormous boost.
Edward Witten
Almost all of the material phenomena which occur under terrestrial conditions are recognized as quantum mechanical consequences of the electrical attraction between electrons and nuclei and of the gravitational attraction between massive objects. We should be able, therefore, to express all the relevant magnitudes which characterize the properties of matter in terms of the following six magnitudes: M, m, e, c, G, and h; M is the mass of the proton, m and e are the mass and electrical charge of the electron, c is the light velocity, G is Newton's gravitational constant, and-most importantly-h is the quantum of action ...
Victor Frederick Weisskopf
The times we live in are alternately derided for their failings and romanticized for their emerging opportunities. It sometimes seems that we now live amid greater violence, greater uncertainty; that the world suffers more conflicts and tragedies; that the poor are poorer and greater in number; that race, ethnicity and nationalism divide us more intractably than ever before.
But that is not so. Human beings are still capable of violence and cruelty. We all succumb to sin. But look back at any preceding century or even just a few decades, and you will see cruelty, violence and misery on a scale that is, with few exceptions, unknown today.
John McCain
There's a rush today to prescribe who is black, to prescribe what our differences, or to ignore what our differences, are. Of course, those of us who came from the rural South were different from the blacks who came from the large northern cities, such as Philadelphia and New York. We were all black. But that similarity did not mask the richness of our differences. Indeed, one of the advantages of growing up in a black neighborhood was that we were richly blessed with the ability to see the individuality of each black person with all its fullness and complexity. We saw those differences at school, at home, at church, and definitely at the barbershop on Saturday morning.
Clarence Thomas
