Particle accelerators have made their way into mainstream media — when the Large Hadron Collider (LHC) at CERN discovered five new baryons “hiding in plain sight,” it was enough to make headlines worldwide. What’s often left out, however, is some of the basic science behind particle accelerator functions, how they’ve evolved over the years and what could come next for these high-speed subatomic smashers.
A Brief History of Making Small Things Go Really (Really) Fast
Particle accelerators work by using electric fields to accelerate groups of particles to high speeds. Two basic models — linear and circular — exist, and both require extremely cold, clean vacuum tubes that enable the particles to accelerate without interference and allow electromagnets to steer and focus the particle beam. So far, scientists have been able to boost particles to 0.99997 times the speed of light before smashing them into metal foil or other objects and recording the results.
As noted by Symmetry Magazine, the first modern circular accelerator was created in 1930 and was less than five inches across. One year later, Ernest Lawrence and M. Stanley Livingston created an 11-inch accelerator. Compare that to the circular LHC at CERN, which is five miles (eight kilometers) in diameter, or the linear accelerator at SLAC National Accelerator Laboratory, which is almost two miles (about three kilometers) long. Accelerators have already made significant contributions to human advancement — some are used to modify the material properties or plastics or harden joints used in semiconductors, while others are used to produce heavily-charged particles for medical treatment or inspect cargo for national security purposes.
Along with discovering new particles, accelerators can also be used to produce quark-gluon plasma (at 7.2 trillion degrees Fahrenheit), which is thought to have dominated the early moments of the universe and is so hot that even quark bonds are broken. Pushing particles to near the speed of light creates unique outcomes: They both gain effective mass and experience time more slowly relative to observers outside the particle accelerator. This can be seen in the lifespans of pi mesons, which typically disintegrate in millionths of a second. Accelerated to high speed, however, these particles can exist for much longer, suggesting that they’re likely experiencing a slower relative time frame.
The Future of Subatomic Smashing
So what’s next for particle accelerators? Stephen Hawking suggested they’re the basis for time travel into the future — go fast enough and everything starts to slow down. While earth-bound accelerators may not work for getting humans up to speed, the action of rapidly orbiting an object (like a circular accelerator) or going really fast in a straight line (like a linear accelerator) has yielded positive results. According to Phys, two projects are currently under review at CERN: A 31-mile (50-kilometer) long linear tunnel and a circular accelerator with a diameter of about 50 to 62 miles (80 to 100 kilometers). Already, researchers have developed a device that can produce electric pulses of 180,000 volts that last exactly 140 millionths of a second with no disruptions from “peak pulses.” And as noted by Popular Mechanics, the development of micro-fabricated dielectric laser accelerators (DLAs) allowed the creation of millimeter-sized solutions that could rival CERN’s performance over just 100 feet. As new storage and transmission technologies develop, the results could be “tabletop” accelerators and the potential for commercialization of these particle producers.
There are more than 30,000 particle accelerators currently in use worldwide, and the number is steadily growing as new scientific breakthroughs occur and commercial applications become less costly. The market here is both shrinking and expanding as research teams look for new ways to speed up subatomic particles, reduce the footprint of facilities and continue to propel humanity into the future. Ready for the challenge?