LHC Data Continues To Disagree With Supersymmetry

decora writes "Pallab Ghosh of the BBC reports on another piece of evidence hitting the beleaguered Supersymmetry community. Scientists at the Lepton Photon conference in Mumbai, India confirmed that extra levels of B-Meson decay have not been found in the LHC beauty experiment. Coming on the heels of a March report in Nature, this news seems to reinforce what many have suspected all along. Dark Matter is probably not explainable through massive shadow particles like squarks and selectrons, and for all practical purposes, the Supersymmetric Extension of the Standard Model of Physics is dead."

Re:Shortsightedness is a weakness

[Baloroth]

How long did they think the world was flat again? And how long before that did they believe thunder was anger from the gods? And how long before that was fire worshiped as magic?

About until the very most primitive scientists, until a semi-reasonable scientific explanation was found, and about the same as the other two, respectively. Seriously, one of the very first people to attempt science (the Greeks) knew the Earth was round, most of them knew thunder was a natural phenomenon but couldn't explain it, and they established fire as one of the four elements of nature (again: not magic but we just don't know how it works quite yet.)

However, if an experiment created explicitly for (among other things) confirmation or refutation of Supersymmetry not only doesn't discover it, but discovers absolutely no sign of it and in fact contradicts it (which I believe these results do), then chances are it's time to go back to the drawing board. Or the math board, in this case.

Re:Overstating

[Anonymous Coward]

I am a particle physicist (with no leanings for or against SUSY variants), and I have to agree totally. Calling SUSY "all but dead" is absurd, at this point.

1. Minimal SUSY has had theoretical difficulties (without needing experimental difficulties) for more than a decade now.

2. The SUSY ecosystem is really quite vast. In some sense, it's a shame that it has such a simple name/acronym. Minimal SUSY is really a rather uninteresting modification to the Standard Model, anyhow.

3. The potential for the LHC to shed light on whole ranges of SUSY models (with or without an answer regarding the Higgs field) is understood by physicists to be something which is more likely to be tested (read: ruled out) at the 14 TeV center-of-mass scale.

The decision run the LHC for two years and *then* upgrade in 2013 was made primarily because of the potential to bracket the Higgs at ~ 4 to 5 sigma with ~ 5 fb^-1 of collision data. Anyone who attended (or read slides from) Chamonix 2010 or 2011 can see this rather plainly.

SUSY remains at the top, BBC article is shoddy

[lumidek]

The BBC article is a piece of shoddy journalism. The LHC has moved the minimal energy at which new physics may occur to higher levels. However, it has done so not only with supersymmetry but with all other possible theories of new physics, see http://motls.blogspot.com/2011/08/supersymmetry-and-irrationality-of-bbc.html [blogspot.com] Supersymmetry remains the most viable candidate for new physics to be found. Only the constrained versions of the MSSM, the Minimal Supersymmetric Standard Model, have been ruled out for a priori sensible values of the parameters. But it's not even true that the whole MSSM has been eliminated. Many other non-SUSY models of new physics have been moved by the data to much higher energies than SUSY - which includes Kaluza-Klein and Randall-Sundrum gravitons, small black holes, leptoquarks, preons, and many others. It's just a flawed interpretation that the data so far present a case to switch from SUSY to something else. If something, they indicate that *no* new theory is needed to describe doable experiments.