Well, as it's old news, here's an old joke to go with it:
"Why do policemen always go around in threes?
One that can read, one that can write, and one to keep an eye on the two dangerous intellectuals."
Bear in mind that SUSY was not intended to be a hack job. The Coleman-Mandula theorem is pretty definitive - if we want an abstraction that looks like QFT, then it has gravity, a gauge group (so in the real world SU(3) x SU(2) x U(1) at any energy scale we're ever likely to be able to detect / care about). SUSY is just the least messy way of extending symmetry in a way which doesn't violate Coleman-Mandula and which could provide constraints on the Higgs mass.
The original hope was that a) some existing particles would be found to be superpartners of other existing particles b) additional superpartners would be discovered relatively quickly.
That was all dashed hope, of course, but my point really is that SUSY didn't start off looking as bad as it does now. I never really believed in it, although some of the algebra was kind of pretty. Of course, having said that, I'll now be forced to eat my words (not for the first or last time), when the LHC finds a Higgs at the last gasp.
"To put it another way, if all the LHC finds is a Higg's and expected results from the standard model, it doesn't actually disprove supersymmetry since any model of supersymmetry has so many parameters that you can tweak a few of them and lift the superpartners back up above the LHC's maximum energies."
Errr, not really. What you said there is pretty much akin to tweaking Newtonian physics by adding small additional terms to produce large-scale structure which matches observations. Or claiming that a geocentric model is fine because, y'know, epicycles can totally cook up anything required to fit observation of the solar system (NB: Please Note: I'm not a gravity bod).
The big problem with a lot of SUSY theories is vacuum stability.
One line of argument goes that something like this: "If there isn't a member of a Higgs n-let below a certain mass, then the vacuum is no longer stable. So by ruling out Higgs at various energies, we rule out certain classes of possible SUSY. As the mass at which we've ruled out Higgs gets higher and higher, the SUSYs which still aren't ruled out get more and more contrived."
At some point (and it's a point which most reasonable people would agree is now not too far off), SUSY stops looking like a like a fundamental law of the Universe and more and more like a hack-job.
Slashdot Mirror
Well, as it's old news, here's an old joke to go with it: "Why do policemen always go around in threes? One that can read, one that can write, and one to keep an eye on the two dangerous intellectuals."
Bear in mind that SUSY was not intended to be a hack job. The Coleman-Mandula theorem is pretty definitive - if we want an abstraction that looks like QFT, then it has gravity, a gauge group (so in the real world SU(3) x SU(2) x U(1) at any energy scale we're ever likely to be able to detect / care about). SUSY is just the least messy way of extending symmetry in a way which doesn't violate Coleman-Mandula and which could provide constraints on the Higgs mass.
The original hope was that a) some existing particles would be found to be superpartners of other existing particles b) additional superpartners would be discovered relatively quickly.
That was all dashed hope, of course, but my point really is that SUSY didn't start off looking as bad as it does now. I never really believed in it, although some of the algebra was kind of pretty. Of course, having said that, I'll now be forced to eat my words (not for the first or last time), when the LHC finds a Higgs at the last gasp.
"To put it another way, if all the LHC finds is a Higg's and expected results from the standard model, it doesn't actually disprove supersymmetry since any model of supersymmetry has so many parameters that you can tweak a few of them and lift the superpartners back up above the LHC's maximum energies."
Errr, not really. What you said there is pretty much akin to tweaking Newtonian physics by adding small additional terms to produce large-scale structure which matches observations. Or claiming that a geocentric model is fine because, y'know, epicycles can totally cook up anything required to fit observation of the solar system (NB: Please Note: I'm not a gravity bod).
The big problem with a lot of SUSY theories is vacuum stability.
One line of argument goes that something like this: "If there isn't a member of a Higgs n-let below a certain mass, then the vacuum is no longer stable. So by ruling out Higgs at various energies, we rule out certain classes of possible SUSY. As the mass at which we've ruled out Higgs gets higher and higher, the SUSYs which still aren't ruled out get more and more contrived."
At some point (and it's a point which most reasonable people would agree is now not too far off), SUSY stops looking like a like a fundamental law of the Universe and more and more like a hack-job.