Supersymmetry Fails Test, Forcing Physics to Seek New Ideas
Some still cling to a vision of an ugly, chaotic super symmetry but haven’t quite reached the point of chanting “Yog Sothoth!” yet.
With the world’s largest supercollider unable to find any of the particles the theory says must exist, Shifman is joining a growing chorus of researchers urging their peers to change course.
In an essay posted last month on the physics website arxiv.org, Shifman called on his colleagues to abandon the path of ‘developing contrived baroque-like aesthetically unappealing modifications’ of supersymmetry to get around the fact that more straightforward versions of the theory have failed experimental tests. The time has come, he wrote, to ‘start thinking and developing new ideas.’
But there is little to build on. So far, no hints of ‘new physics’ beyond the Standard Model — the accepted set of equations describing the known elementary particles — have shown up in experiments at the Large Hadron Collider, operated by the European research laboratory CERN outside Geneva, or anywhere else. (The recently discovered Higgs boson was predicted by the Standard Model.) The latest round of proton-smashing experiments, presented last week at the Hadron Collider Physics conference in Kyoto, Japan, ruled out another broad class of supersymmetry models, as well as other theories of ‘new physics,’ by finding nothing unexpected in the rates of several particle decays.
‘Of course, it is disappointing,’ Shifman said. ‘We’re not gods. We’re not prophets. In the absence of some guidance from experimental data, how do you guess something about nature?’