Negative results are important and the LHC just shows that. While the LHC hasn’t been able to find the Higgs Boson with absolute certainty as yet, it has done physics great service by eliminating a lot of different possibilities and put stringent bounds on existing theories. The CMS collaboration at LHC has just released a paper reporting their findings related to the existence of hidden extra dimensions. This is crucial to the very fabric of string theory.
The CMS hasn’t found anything in their data that indicates that extra dimensions exist. The team has looked at the energy range of 2.3 to 3.8 TeV, which is the typical collision energy of protons, when the LHC runs at 7 TeV beam energy. The LHC recently upgraded to 8 TeV, 1 TeV up from the usual, but there is little hope of finding things at that energy. We can only wait till the LHC resumes its run after the break it is scheduled to take in a few days. It will be back at 14 TeV and maybe then we can get something on extra dimensions.
And the Tevatron adds to the misery…
Not only the LHC, even the Tevatron data eliminates the presence of extra dimensions, at least at low energies. The Tevatron is dead, but the data is still there and the D-Zero detector team is looking at the energy range around 260 GeV and have found nothing.
So far, the theoretical bounds on the energies at which particles might couple to extra dimensions have large errors. So this result really tells us what the lower limit for any experiment searching for extra dimensions should be.
The LHC is continuing to negate anything beyond the Standard Model. It has got good data to verify the one last piece of the Standard Model – the Higgs Boson – and the search is in its last few days. It seems that the emergence of physics beyond the Standard Model, except in the neutrino sector, isn’t happening at the moment.