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Rather surprised I haven't seen many questions or discussion regarding the rumored confirmation of the Higgs field. As I understand it, the energies where they saw things were actually quite a bit higher than they had predicted (guessed?).

  • What does it mean that the energies where it was detected are higher than anticipated?
  • Does it impact the way we understand the standard model to work?

EDIT (Moshe, December 13): Now that the announcement is out, these questions and the more general one of potential implications of this for various ideas of BSM physics can be answered here.

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This won't be a discovery, but perhaps a strong hint. We will know much more in 72 hours, so maybe it's best to ask then. For now, though: it would be perfectly compatible with the Standard Model and nothing else. It would also be compatible with supersymmetry, although rather heavier than one might have expected for "typical" low-energy supersymmetry. –  Matt Reece Dec 10 '11 at 16:50
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In my mind there are already plenty of places for both rumour mongering and complaining about said rumour mongering. Where we can do something new is a discussion of the implications of the announcement (on Tuesday), including that of the Higgs mass range preferred by the LHC. So, personally I’d love to see a question (even this question) focused on the physics of the Higgs and forgetting about the sociology and the “inside baseball”. Maybe a reformulation of the question, or one good answer, could set the right tone. –  user566 Dec 10 '11 at 18:14
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Dear @Matt, nice mini-answer, +1. One could also say that if it is "perfectly compatible with the SM", the mass is lighter than one would expect for a "typical" non-SUSY Standard Model (by 15 orders of magnitude, in fact, to add a funny twist to it). Incidentally, there will be evidence and "candidates" but the press release won't contain the word "hint". Do you want to make a bet? ;-) –  Luboš Motl Dec 10 '11 at 18:56
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@Larian: I think you have a good question there, no need for me to rephrase it. Most of the people able to give a good answer probably know already what is to be announced on Tuesday. –  user566 Dec 10 '11 at 20:10
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"I'll soon be turning around corner now" (Queen, Show must go on). –  Vladimir Kalitvianski Dec 12 '11 at 10:12

1 Answer 1

up vote 3 down vote accepted

I do not think it is fair to say "the Higgs looks like it's going to be at higher energies then anticipated". In fact, my money was on 160 GeV, based on models coming from noncommutative geometry. But the basic constraints on the Higgs mass from the standard model were really not very good (the following comes from the review article of Djouadi, 0503172v2). Short story: Unitarity starts failing around 900 GeV, perturbation theory fails around 700 GeV. A lower bound can be gotten by requiring that the Higgs quartic coupling remain positive, which gives $M_H> 70$ GeV. This depends on the cutoff-scale; the 70 GeV comes from assuming a 1 TeV cutoff scale. If the SM is valid up to GUT scales, this rises to $M_H>130$ GeV.

So, although the current values for Higgs are actually just below that 130 GeV, I think it's not fair to make any statement except that "it seems fine for the standard model" - it's too early to say "the Higgs mass implies new physics". All of these estimates are based on measured parameters such as the Top mass, which has it's own uncertainty associated with it. There is also the fine-tuning problem, but the above bounds generally give the same or slightly better estimates then that.

If someone wants to mention SUSY implications of a $\sim 125$ GeV Higgs, be my guest - there certainly are some. But SUSY can't possibly be real anyway, so I'm ok not knowing them ;-)

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