Cause me alarm.

I deplore articles

Pro- or anti-particles. --Allen Herzog

Don't pick on small particles

You find in my articles.

My next theory, if true,

Has some bigger than you!   --Sheldon L. Glashow

Sheldon Lee Glashow is a charming man. Five days a week the tall, pot-bellied, cigar-puffing physics professor shuffles into his third-floor office, plunks himself down behind his desk, strikes a match to a gigantic role of cured tobacco leaves and plies his trade--pondering the fundamental constituents of matter. And the profundity of Glashow's thoughts have made him a founding father of the theory of "charmed particles."

What is modern particle physics--or, for that matter, Sheldon Glashow--all about? Glashow gives a pithy, if somewhat superficial account in the introduction to his Oct. 1, 1975 article in Scientific American, "Quarks with Color and Flavor." Glashow writes:

Atomos, the Greek root of 'atom,' means indivisible, and it was once thought that atoms were the ultimate, indivisible constituents of matter, that is, they were regarded as elementary particles. One of the principal achievements of physics in the 20th century has been the revelation that the atom is not indivisible or elementary at all but has a complex structure. In 1911 Ernest Rutherford showed that the atom consists of a small, dense nucleus surrounded by a cloud of electrons. It was subsequently revealed that the nucleus itself can be broken down into discrete particles, the protons and neutrons, and since then a great many related particles have been identified. During the past decade it has become apparent that those particles too are complex rather than elementary. They are now thought to be made up of the simpler things called quarks. A solitary quark has never been observed, in spite of many attempts to isolate one. Nevertheless, there are excellent grounds for believing they do exist. More important, quarks may be the last in the long series of progressively finer structures. They seem to be truly elementary.

Glashow has a large, well-lit office in Lyman laboratory, near the Law School. A huge floor-to-ceiling bookcase filled with copies of the Physics Review and unbound notes lines one wall. Some colorful charts of fish from a local food-packing company and a map of Boston decorate another. The third has a blackboard on it covered with scientific-type scribbling and a picture of Glashow and Howard M. Georgi III, associate professor of Physics and frequent collaborator with Glashow. Georgi and Glashow face each other in the picture, bemused. A cartoon-type bubble pasted on the picture depicts them berating each other with the caustic phrase, "You dummy!" A sketch of Einstein and an enlarged photograph of a delicate white web of spirals on a black background decorate the fourth wall. Cross-country skis stand in the corner.

Glashow sauntered in, put his feet up on his desk, and began to explain atomic physics:

The quantum mechanics of the '30s, formulated by Schroedinger, Heisenberg and others, made astonishingly successfuly predictions about such atoms. Physicists turned their attention from the atom to the nucleus.

The force holding the nucleus together was still an enigma. Theoretically, a nucleus should fly apart since it is composed of identically charge particles. The gravitational attraction of two protons is negligible when compared to their electric, or electromagnetic, repulsion. In fact, atomic nuclei are very tightly bound. Confronted with an otherwise successful theory and this apparent empirical contradiction, physicists simply invented another force, which protons and neutrons feel, but to which electrons are immune. Because it is so strong, they named it the "strong" force.

Here a short digression is necessary. Modern quantum mechanics describes the forces between particles in terms of other, "mediating" particles. The mediating particle of gravity is called the graviton. The mediating particle of the electromagnetic force is called the photon. And the mediating particle of the "strong" force, proposed in 1934 by the Japanese physicist Hideki Yukawa, is called the "pion."