In a 2.4-mile-long tunnel built in the shape of a racetrack, scientists plan to race ion beams instead of horses. Two gold ion beams, traveling almost at the speed of light, will cross each other at four junctures, where they will collide head-on. The collision will produce a temperature ten thousand times that of the sun --a trillion degrees. Then, hopefully, as the particles fly out from the area of collision, the objective will be obtained: the re-creation of the big bang.
A team from the Weizmann Institute, headed by Prof. Itzhak Tserruya of the Particle Physics Department, is participating in the biggest and most extensive effort yet to answer one of the most fundamental questions of our existence: What happened after the big bang? Walking around the collider complex at the U.S. government's Brookhaven National Laboratory on Long Island with some of the leading scientists in this multi-pronged project (in which 430 scientists from 11 countries are participating), one can feel the almost childlike excitement of these scientists in the days leading up to the initial experiment. Reproducing the big bang is the kind of experience that generations of physicists before them could only dream of.
Fulfilling a critical role in the project, the Weizmann Institute scientists have designed and built 16 particle detectors; they will be used in the experiment to detect particles flying out of the collision area. With the highly sensitive and very strong, yet lightweight, detectors installed near the collision site, it will be possible to detect the interactions going on in the site and to identify the particles. The electronic circuitry of these detectors will identify the precise three-dimensional location of the particles as they come flying out from the collision. This information will then be combined with that from other detectors to calculate the energy of the particles and their subatomic identity.
Scientists theorize that quarks and gluons are the smallest, most basic building blocks of all matter. Microseconds after the big bang, in conditions of very high temperature and pressure, these quarks and gluons were in a special state of matter called quark-gluon plasma. According to the theory, this plasma state immediately began to cool down and then condensed into the nuclear particles with which we are familiar, protons and neutrons. Gradually, over time, these particles became atoms, which later combined into molecules, from which all forms of life eventually emerged.
The experimental apparatus at Brookhaven used to re-create the big bang, is called a Relativistic Heavy Ion Collider (RHIC). The RHIC's accelerator is the most powerful in the world for use with heavy gold or lead ions used in nuclear experiments. By colliding two gold nuclei, the temperature will be so high and the pressure so intense, it is believed that the nuclei of the gold ions will go through a rapid transition phase and thus be transformed into the quark-gluon plasma. If this happens, a core component of the big bang theory will finally be proved.
The physicists involved in the Brookhaven project are used to being asked about the social value of the basic research they are doing. With obvious passion one of the researchers in the project explains to his visitors, as he leads them through the underground tunnels of RHIC, that pursuing answers to theoretical questions is the lifeblood of science. What motivates him, Tserruya, and others involved in the project is curiosity about the universe we live in. Without that curiosity and the directed energy that comes from it, there would be no Internet, no MRI, no high-speed trains, and no advances in cancer treatment. The applications of scientific discoveries create wealth and generate wonder about the power of technology. Curiosity about basic science, however, is the spark that lights the flame.