Sunday, October 2, 2011

A Handful of Colliders

The shutdown of the Tevatron (image), America’s only large hadron collider, on September 30, 2011, brings the number of LHCs worldwide down from two to one. Western culture has entirely dominated elementary particle physics at the experimental level—the level where proof of the particles’ existence and behavior can be physically determined. The only accelerators are in the United States and at CERN’s facility in Switzerland. CERN is operated by 20 European member states.

This research involves causing particles to accelerate to very high speeds, read energies. When they have reached top speed, they are caused to collide, and the moment of collision is then recorded. Careful observation and measurement of collision points and the tracks left by particles gives us insights into the strange “existents” that make up all matter.

The size or power of a collider is measured in electron volts. The Tevatron was named the Tevatron because it is capable of generating 1 TeV of power, thus one teravolt of energy, thus one trillion volts. The volt is a measure of electrical pressure or flow. The numeric succession is from the simple electronvolt (eV) to deca (10s), hecto (100s), kilo (1000s), mega (millions, MeV), giga (billions, GeV), tera (trillions, TeV), and peta (quadrillions, PeV). We’ve not reached the peta stage. Our largest, the CERN-LHC, has a 14 TeV rating, each colliding particle carrying 7 TeV. By way of grasping the monstrous energies involved, ponder that the energy of light ranges between 1.6 to 3.4 eV. At room temperature, a single molecule in the air has 0.04 eV of kinetic energy.

Here in the United States we’ve struggled to excel, and Tevatron was our winner. Isabelle, at Brookhaven National Laboratories, proposed at 400 GeV, never got off the ground; it was begun but then got cancelled in 1983. Tevatron was built in 1987. We built the Relativistic Heavy Ion Collider at Brookhaven in 2000 (17.7 GeV when used on protons); it is still operational. CERN, which had built two earlier colliders (1971, 1981) before we built our first, introduced its Large Hadron Collider (14 TeV) in 2009; currently it is the most powerful. Our own Superconducting Super Collider, which was to have been built in Texas, would have produced 40 TeV of energy, 20 TeV per colliding hadron. The project was cancelled in 1993. CERN is now working on a proposed Super Large Hadron Collider, envisioned to begin operations in 2019. Herewith a list of our handful of colliders obtained, like the image of Tevatron, from Wikipedia (link).

The scientific interest is certainly present in the United States. The collective political will is not. I’m powerfully reminded of a book about Hellenistic science I’ve recently read. It is The Forgotten Revolution by Lucio Russo. Russo argues that Rome, unlike Hellenistic Greece, had had no gut-level interest in science as science. It was interested only in power and its administration. These colliders represent pure science. If they promised a handy way to cause little Big Bangs deliverable by drone, then perhaps Congress might be found at the plate; not until then.

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