What is a Superconducting Supercollider?

The Superconducting Supercollider, or SSC for short, would have been a particle accelerator of gargantuan proportions, nicknamed the 'window on creation' for its proposed ability of recreating some of the conditions present at the time of the Big Bang itself. It was to be built near Waxahachie, just outside Dallas, Texas, USA. It was first conceived of in 1978 at workshops of the International Committee on Future Accelerators where a powerful particle accelerator was discussed. Then in 1982, the Snowmass Summer Study that was sponsored by the Division of Particles and Fields of the American Physical Society discussed the project further. It was predicted that it would have taken around nine years to complete (from 1991 to 2000), costing nearly $12 billion, which was over twice the original estimate.

The device would have accelerated beams of protons (particles found in the nuclei of all atoms) around an 87km (54 mile) long tube until they were travelling extremely close to the speed of light (300,000km/s). Some beams would travel clockwise, others anti-clockwise; thus they would collide at an energy of 40 trillion electron volts (40TeV), revealing a burst of tiny particles that special detectors would analyse. The planned 40TeV figure was double the original expectation and it transpired that organising the project at large was logistically problematic.

Electron Volts

A word should be said about the unit called the Electron Volt before continuing into the depths of the sub-atomic world. The Electron Volt (eV) is the unit of energy used for giving the mass or energy of a particle. The reason the same unit can be used for both mass and energy is that by Einstein's famous equation E=mc², mass is energy. So if it is being used to denote the mass of a particle, the unit should be expressed as eV/c².

Anyway, an Electron Volt is how much energy or energy transfer (work) there is necessary to move one electron through a field of one volt. As energy, it can also be expressed as 1.602*10^-19 joules (if you are not familiar with standard form this is 0.0000000000000000001602 J). Since this is such a small unit, it is more common to see Mega Electron Volts (MeV, a million times larger) or even Giga Electron Volts (GeV, a thousand million times larger). 100-watt light bulbs require 100 / (1.602 * 10^-19 * 10⁶) MeV = 6.24*10¹⁴ MeV every second.

To put things into perspective, the mass of an average-built human in Mega Electron Volts is 4*10³¹MeV/c². And to put this further in perspective, to obtain this amount of energy you would need to eat the equivalent of nearly 13 trillion plain chocolate bars! Well, it is in the name of science isn't it?

In order to get the protons to move in this way, exceedingly strong magnetic fields have to be used, created with magnets made of a specially reinforced material that would stop the field from warping the metal of the magnet itself. They were supposed to be so large as to be hundreds of thousands of times more powerful than the magnetic field of the Earth! In turn, the magnets would have to be free of thermal and electrical resistance in the coils. Since resistance is caused by other particles impeding the progress of electrons through wires, the best way to stop it is to cool the coil close to absolute zero temperature (-273.15 degrees C) so that the particles can barely move.

What Was its Purpose?

It was hoped that the SSC would ultimately provide evidence for one of the greatest theories of the century: superstring theory (or M-theory). M-theory is an attempt at unifying Albert Einstein's celebrated theories of relativity, with the new revolution of quantum mechanics, two theories that seem to be inherently incompatible. M-theory does this by stating that all sub-atomic particles are not just 'points', but tiny vibrating membranes of more dimensions than it is possible to see.

The trouble with M-theory was that nobody could think of a way of proving it, since these membranes would be far too small to detect even with the most powerful of microscopes. The aim of the SSC was to try to discover some particles in the proton collision debris that might give a pointer to the correctness of M-theory's ideas, including the existence of so-called super-particles that have been so far hypothetical. They might also have detected a particle called the Higgs boson, which would have shed light onto many other mysteries of nuclear physics because it is predicted in the highly esteemed Standard Model of Particle Physics, as well as the hypothetical axions that might solve the dark matter issue.

Like most physics experiments, the SSC could never have definitively proved any scientific theory; it could only have provided some experimental evidence that would support the theory. It would also have been impossible for the SSC to produce an answer to everything. The energy necessary to create a black hole or wormhole, which would allow us to probe higher dimensions, is a quadrillion times larger (one million billion) than what the SSC would have been capable of.

You are probably by now aware of the use of the conditional tense throughout the article. This is because the SSC was cancelled in 1993 by the US Congress, who considered that the equally expensive International Space Station could not be built as well as the SSC. Twenty-two kilometres (14 miles) of the tunnel had already been dug, costing $2 billion.

The USA wanted to be at the forefront of cutting-edge science research when the SSC was first proposed. It was initially seen as having so many political and social advantages that it was worth the money (that was when its target cost was $8.25 billion). About 7,000 jobs were created by the SSC and contracts were made in 48 of America's 50 states, while 23,000 students enrolled in mathematics and science courses that involved the SSC. More than 100 American universities were hoping to be involved in the SSC's research. The magnet tests had passed successfully, the rest of the colliding tunnel was contracted and all tasks were on schedule. Even China and India had signed contracts to get involved. There was a possibility that the SSC would help in research on proton-beam cancer therapy and even an insight into the structure of the AIDS virus.

Yet despite all of this work and all of these advantages, there is now a $2 billion hole in Texas that has been used only for storing Styrofoam cups for many years. The company ProTac Global Inc., based in Texas, has now bought part of the site for anti-terrorism firearms training (for a mere $8 million, which they claim is larger than the asking price). The conversion of the site of the device, which could have shown the world its most fundamental workings, to a military organisation was to be completed on the first anniversary of the 11 September, 2001 attacks.

Roy Schwitters was the director of the SSC project and has now moved on to be a physics professor at the University of Texas in Austin. He is saddened by the decision to turn the site into the military zone, especially after the hard work of the physics community in trying to resurrect the project. Three other science-related uses for the site were suggested before ProTac (medical radiation research, a cryogenics centre and a super-computing centre) but all were rejected, again because of the high costs.

Conclusion

Does the SSC provide an insight into the mindset of the US government, or is physics just getting too unrealistically expensive? You decide: would you have a site for teaching people how to defend themselves against terrorists, or a device that is the most audacious of its kind that would explore the fundamental nature of space and time itself?