.
July 4th, 2012
02:47 PM ET
Higgs boson discovery
AFP/Getty Images
It's a big day for particle physics! Scientists at CERN believe they have found a fundamental building block of our universe: the elusive Higgs boson.
You may know it by another name. It's also called the "God particle."
Today's announcement is just a preliminary result, though scientists say it is "very strong."
But what exactly is the Higgs boson... And why do we care about it?
Scientists believe it is the particle that gives all matter its mass. Finding it would fill a huge hole in the Standard Model of physics. That theory explains how our universe works.
Wow in my life time.... I am impressed with the LHC!
"God particle"?!
Why people have the need to mix their superstitions and dogmas with scientific matters?
Any serious scientist can confirm that there is no relationship of this Higgs boson or any other sub-atomic particle with any mystical or supernatural issue.
We have to stop accepting the mystical and religious preachers to confuse people with this kind of misinformation every time science offers any advance. The same kind of proselytisers that create this kind of nonsense as "the God particle" are those who try to deny any scientifically proven fact that challenges their religious dogmas. For example the "creationists" try to discard all biological, anthropological and geological evidence that the universe is about 13.7 billion years old, because it does not match the fairytale of the biblical Genesis!
The media in general should not give space for this kind of mystification.
Hi Marc Sher (who I used to know at Santa Cruz many years ago),Though the basic thrust of your argemunt is right (i.e. that scalar fields are problematic at high energies), it is not true that the quartic Higgs coupling becomes negative. I am pretty sure you are thinking about Landau's pole. I hope Peter W. will indulge my discussing the technical issues, so to avoid causing too much trouble, I'll be brief. He may permit my comment because they directly concern the Higgs mechanism.Landau's formula for the effective coupling is only good for small couplings. It breaks down at high energies, where it predicts the sign change. The pole/sign change is fictitious. The real problem is that if the coupling at high energy (say with a Planck-scale cut-off) is not fine-tuned to some enormous value, the coupling at the TeV scale is nearly zero. This can checked by the renormalization group in 4-epsilon dimensions, by 1/n-expansions and by numerical simulations. It is also strongly indicated by some rigorous results about triviality, but these don't quite work in four dimensions. There is no change in the sign of the coupling. Some field-theory books present the Landau pole as gospel, even though it is completely unphysical. The real problem is triviality/fine-tuning.
Jeff,You can look up the expected width of the bump, I think it's very rgulhoy 2 GeV or so. Remember, right now the bumps are near the limit of statistical significance, not something well-resolved where you can precisely locate a peak. The numbers being quoted are also not as precise as possible. It could very well be that the ATLAS peak is near 125.5, the CMS one near 124.5. So, the small discrepancy in mass value is probably not significant.Yonghun Park,As you accumulate better statistics, if there's a Higgs there, the statistical significance should increase. If there's nothing there, it should decrease. Both statements are probabilistic, but with very high probability if substantially more data is accumulated.
Interesting rumours, ieendd, and I am confidentthe Higgs will be found in the range 122-132 GeV, havingpredicted its mass together with the top quark massin a composite model, before either top or Higgs weredetected. But I'ld point out there were similar rumoursof an excess in the b anti-b channel indicating a Higgsin the range of 130-140 GeV just a couple of months back(personal communication from W. Marciano). It was a similardeal, a couple of sigma each in CMS and Atlas, which addedto a bit more than 3 sigma. It went away of course.My last look at the 2 gamma data, with abouthalf of the total data set analysed showed points aboveand below the theoretical continuum, and nosign of a bump whatever. The SM Higgs width at thismass is so small that I don't even remember the numberbut I believe it's on the order of 1 MeV. So in this casethe width of any bump in the 2 gamma mass spectrumwill be determined by detector resolution, on the orderof 5 GeV. There was an extra factor of two availablein the integrated flux not analysed at that time, butthat only gives 40% better resolution of any bumpat 125GeV. So I can't believe this will be conclusive.A SM Higgs this light just escapes the vacuumstability and metastibility (due to finite temperatureeffects in the early universe) if new physics onlyappears near the Planck scale. So it's premature for Kane and the supersymmetriciansto be rejoicing, I think. They should rather be worryingabout the absence of supersymmetry at 95% confidencelevel, below about 1 TeV. Exciting times! about 50%