![]() ![]() Not only does it fail to account for gravity (this is the purview of general relativity), it cannot explain why matter is more abundant than antimatter. The field associated with it confers mass on the other particles, and ties the Standard Model together.īut, though it is one of the most tested, most successful scientific ideas of all time, the Standard Model is not a complete description of the universe. The discovery of this, in 2012, using the then recently opened lhc, was a triumph of scientific prediction, the particle having been described theoretically by the eponymous Peter Higgs in 1964. Bosons include photons, which carry the electromagnetic force (and are the particles of light), the aforementioned w boson, the gluons that hold atomic nuclei together via a second, strong nuclear force, and the Higgs. Bosons carry the forces which hold that stuff together, or sometimes push it apart.įermions divide into leptons, quarks and their antimatter equivalents, which are identical to normal matter but with opposite electrical charges. The Standard Model describes two broad classes of particles-fermions and bosons. But there was until recently a widespread belief that lurking behind this door would be a predicted step on the journey, called Supersymmetry. Their ultimate goal is to unify the Standard Model and general relativity into an overarching “theory of everything”. Practitioners have been battering on this portal since the Model was put together in the 1960s and 1970s, to no avail. If they do survive scrutiny, these three findings may go into future textbooks as the keys which unlocked the door marked “Physics beyond the Standard Model”. But all of them are close enough to this threshold to be eye-catching (Dr Patel’s, for example, is 3.1-sigma), and thus worthy of further work to attempt to reach the magic value of five. Five-sigma equates to a probability of around one in a million that something of interest in fact happened by chance. None of these results, it must be said, yet quite reaches the gold standard of confirmation, known as 5-sigma (ie, five standard deviations from the mean) which particle physicists normally demand before they will call something a “discovery”. The third time, as Ian Fleming opined through the mouth of Auric Goldfinger, does look like enemy action. The lhc’s latest run may provide the wind needed to fill them properly.įermilab’s contributions to the anomaly list, announced respectively in the Aprils of 20, are that the magnetic properties of muons wobble around at frequencies which do not match predictions and that the mass of another Standard Model particle, the w boson, which carries the weak nuclear force that is responsible for a form of radioactivity called beta decay, seems larger than predicted. After a long period in the doldrums, the sails of the ship of physics are rustling in the breeze. Two other Standard Model-violating results, from cern’s American frenemy Fermilab, have also been published recently. Nor is the b meson anomaly, as it is known, the only recent result that might attract the attention of the prize-awarders at Sweden’s Royal Academy of Science. This model has, with assistance from the general theory of relativity developed earlier by Albert Einstein, held physics together for around half a century. A violation of lepton universality would be a crack in what is called the Standard Model, and therefore Nobel prizewinning stuff. To a physicist it is practically an invitation to book a flight to Stockholm. To the person in the street this may not sound a big deal. ![]() Instead, Dr Patel’s team found that only 85 muons were emitted for every 100 electrons. For the forces that govern them, there is no difference between the two, an idea called “lepton universality”.īut that is not what the tallies counted by the lhcb showed. ![]() According to the accepted rules of particle physics, such decays should yield as many muons as they do electrons. One way in which these mesons decay is by the transformation of the bottom antiquark into a so-called “strange” antiquark and a pair of leptons, a different class of fundamental particle that includes electrons and their more massive cousins, muons. b mesons come in many varieties, but all have a constituent called a bottom antiquark. The lhcb team has spent the best part of a decade measuring how subatomic particles known as b mesons decay into lighter particles. ![]()
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