Standard and Stringy Particle Theory

Scientific curiosity has lead physicists to break an atom into electrons and the nucleus, the nucleus into protons and neutrons. Inside the protons and neutrons are still smaller parts. This brings us to the world of elementary particles, particles for short.

At the smallest measurable length scale, 10 to the power minus seventeen meters, there are three families of pointlike quarks and leptons, which build up all (ordinary) matter. Each quark comes in three forms, called color: red, green or blue. These elementary particles interact via boson exchange corresponding to the electromagnetic, weak and strong interactions. The behavior of these particles can be described by a beautiful mathematical theory called the

standard theory

Going beyond the standard model, researhers are using their math skills and intuition to formulate the "Theory of Everything" (TOE). This theory, when completed, would describe everything in nature starting from the Big Bang through galactic and solar system formation to cell biology (and consciousness, according to the bravest!). - Surely, our Creator had at least one choice for a beautiful universe for us to live.

Pie Chart This is not, however, all. Measurements of the cosmos surprisingly indicate that

4% of the matter in the universe is ordinary matter (atoms, ie. quarks and leptons),
23% is dark matter and
73% is dark energy, implying accelerated expansion of the universe, and non-zero cosmological constant.

The newest measurements, as of Feb 10, 2003, come from the NASA WMAP satellite, Wilkinson Microwave
Anisotropy Probe (see their pic on the right). Somewhat surprisingly, 96% of the universe's matter, or energy,
is of unknown form ! Before clicking to the WMAP web site see also a cool picture of the time history of the observable part of the universe.

It is fascinating to think how close - or far ! - we are in understanding these matters with strings (open or closed), branes (two or higher dimensional membranes), M(ystique)-theories in 11 dimensions, inflating bangs and multiple universes.

Felt a touch of spark? Then make a net serch with a keyword like "superstring" or go to the "official" site of

superstring theory at Caltech, or to
quantum gravity in Cambridge, UK

There are some nice mpg-movies of string world events, eg. here (DAMTP).

A very readable concise review , dated Dec 19, 2002, of the string theory by Ed Witten of Princeton, one of the top string theorists, is recommended.

As the Web was originally designed at CERN for scientific information sharing and distributing it comes as no surprise that techical publications of particle physics and related fields have for a number of years been available on the Internet as soon as the author(s)transfer the text/image files from their computers to CERN or arXiv (Cornell & mirrors) e-print archieves. Webcasts, both live and archieved, are becoming available, eg. from CERN. An excellent, all covering particle physics information web site has been compiled at SLAC Library.

A random pick from the arXiv particle theory page, and from the New York Times Science section.

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