Today the SSC buildings are occupied by Waxahachie chemical manufacturer Magnablend. Access shafts have been filled in, and what tunnel remains collects rainwater. Amidst endless budget problems, Congress flits with large science projects like the James Webb Space Telescope, canceling and then reversing as costs and completion dates lengthen—scenarios eerily familiar to the SSC’s tragic path. The European-based CERN was the major focus of the 2013 physics Nobel to Peter Higgs and François Englert, and it is Japan, not the U.S., talking of hosting an International Linear Collider.
Despite fears at the time, the SSC did not herald the end of U.S. particle physics, by any means. (In 1993 the Division of Physics of Beams made up 3.4 percent of the American Physical Society’s membership; this year it is 2.3 percent, a decline of 361 members.) Physics faces a host of new questions, such as the nature of dark energy, the identity of dark matter and the subtle properties of neutrinos, not all of which can be answered by ever more powerful accelerators. But others can, such as the exact properties of the Higgs boson and the ever-tantalizing possibility of supersymmetry. The current design of the LHC places a hard energy limit of 16 TeV (8 TeV in each beam), and no physics above that threshold can appear, no matter how high its beam intensities. The SSC would have punched at a higher weight.
Yet Riordan believes the U.S. made a mistake by reaching for such a high energy at the SSC, when a lower energy might have discovered the Higgs particle, as recent experience has confirmed. “The high-energy physics community insisted on the largest possible machine, so large it didn’t have the skills to manage it,” he says. “American physicists wanted to leapfrog the Europeans and reestablish their leadership in high-energy physics—which was a political reason, not a physics reason.”
Many believe accelerator physics still has an important role to play, such as with a linear collider that will by necessity be a worldwide effort. “I do not believe that we can make significant progress without also pushing back the frontier of high energy,” Nobel laureate Steven Weinberg wrote in an essay titled “The Crisis of Big Science” in The New York Review of Books last year. “So in the next decade we may see the search for the laws of nature slow to a halt, not to be resumed again in our lifetimes.”
The SSC was an epic project that ended in failure. The U.S. has yet to stride again its own once prominent footsteps; but perhaps worse, it no longer dares to dream in color. Whatever the future for high-energy physics the U.S. and the world, the hulking beast that would have been the Superconducting Super Collider will not soon be forgotten.