Maybe not, but SUSY (short for Supersymmetry) certainly seems to be in a coma.
Supersymmetry is a family of proposed extensions to the Standard Model of Particle Physics hoped to address several shortcoming in the Standard Model, including the Hierarchy Problem (why quarks are so much more massive than electrons, which in turn are so much more massive than neutrinos, and why the various fundamental forces have vastly different strenghts), reconciling General Relativity with quantum theory (i.e. quantum gravity), and unification of electroweak interactions with the strong nuclear force. Additionally, SUSY provides candidates for dark matter, as well as providing a mechanism for electroweak symmetry breaking. In short, SUSY, if valid, offers a way to fill in a LOT of gaps.
SUSY theories first came to prominence in the early 70’s, and gained considerable traction in the 80’s. It is even incorporated into many variants of string theory (with such variants referred to as superstring theories). Much is riding on SUSY, and one of the reasons for the creation of the Large Hadron Collider at CERN is to put SUSY to the test.
And those tests are not going well. SUSY predicts the existence of supersymmetric partner particles (such as squarks, selectrons, photinos, gluinos, etc.) corresponding to the normal SM particles (quarks, electrons, photons, gluons, etc.) but at higher masses. The lighter of these superpartners should be within mass ranges accessible to the LHC. Thus far,there is no sign of them. Recent results from the LHCb collaboration have ruled out a considerable chunk of the parameter space for SUSY in their studies of the decay of BS and BD particles. Furthermore, results from the LHC search for the Higgs boson have put tight constraints on SUSY models as well.
SUSY may not be dead yet, but she does appear to be pretty ill….
- SUSY Still in Hiding | Not Even Wrong
- Much food for thought at major physics conference | Quantum Diaries
- Rencontres de Moriond EW 2012: Seeing less would be just as good – CERN Bulletin
- Rencontres de Moriond EW 2012: Impact of a Higgs boson on supersymmetry – CERN Bulletin
- The Incredibly Shrinking Supersymmetry
- Still Waiting for Supersymmetry | Not Even Wrong
- SUSY And The Silence Of The (Roasted) Lamb
- Where Stands Supersymmetry (as of 4/2012)? | Of Particular Significance
- Is Supersymmetry Dead?: Scientific American
- The Plot Of The Week – No SUSY In New CMS Search
- The Smell of SUSY | Not Even Wrong
- LHC Experiment Finds No Signs of Supersymmetry | Wired Science | Wired.com
- Supersymmetry: The Future of Physics Explained | Wired Science | Wired.com