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LHC Breaks Supersymmetry’s Beauty

Image Credit: Spiro 4 Stuart Daly/Dutch Uncle Agency

With possible but not yet definite and verifiable news of gaining some understanding to the elusive Higgs Boson, what would happen to the other theories that have been submitted? More specifically the other favored theory. In this limited article, NS explores the other side of the story and what could come of it.:

In July, at a particle physics conference in Grenoble, France, Nobel laureate George Smoot seemed to be channelling the spirit of Thomas Huxley. The scrappy 19th-century champion of Darwin’s theory of evolution by natural selection once spoke of “the great tragedy of science - the slaying of a beautiful hypothesis by an ugly fact”. Smoot, a cosmologist who made his name studying the afterglow of the big bang, thinks this is just the drama now playing out in particle physics.

Particle physics has a beautiful theory, known as supersymmetry. More than three decades in the making, its elegant mathematical structure was intended to replace the “standard model”, the eminently serviceable but sometimes creaky and in parts aesthetically unpleasing theoretical construct that is currently our best description of matter’s fundamental workings.

Supersymmetry’s beauty is now meeting some ugly facts emerging from the Large Hadron Collider, the gargantuan particle accelerator situated at CERN near Geneva, Switzerland. Supersymmetry predicts a whole slew of new particles, and by most reckonings the LHC should have started producing some of them already. But it hasn’t. That throws up some big questions. Is supersymmetry really the right answer? If not, what is?

Supersymmetry - SUSY to its legion of fans - has long been seen as a panacea for the standard model’s ills. Back in the early 1960s, one of the theories that went into making the standard model faced an embarrassment. It could not explain how elementary particles, things such as electrons and the quarks that make up protons and neutrons, get their mass. It predicted none of them had any mass at all.

A workaround, arrived at from several angles in 1964, was to postulate that an all-pervading field exists with which elementary particles interact differently, giving each a unique mass. This was the Higgs field, named after one of its progenitors, Peter Higgs of the University of Edinburgh, UK.

The Higgs mechanism was neat, but created its own problem. Experimental clues indicated that the mass of the “quantum” of the Higgs field, the Higgs boson, was between about 114 and 180 gigaelectronvolts (GeV) – exactly the range in which the LHC is currently feverishly seeking the particle, with as yet only tantalising hints. The theory, though, made it something like a billion billion times bigger. This gigantic discrepancy came to be known as the hierarchy problem.

Article: The truth hurts: LHC breaks supersymmetry’s beauty