Physics at the LHC

Abstract

The LHC will be the first accelerator to explore directly the TeV scale. Any new energy range takes us deeper into the structure of matter, but there are good reasons to expect the TeV range to be particularly interesting, since there are several indications that it might reveal new physics. One is that we expect it to reveal the origin of particle masses, which are presumably due to the Higgs mechanism [1] but possibly with the aid of additional particles beyond the single Higgs boson of the minimal Standard Model, such as supersymmetry [2]. These seem to be required, for example, to stabilize the energy scale of the weak interactions below 1 TeV [3]. Another indication of new physics at the TeV scale may be provided by attempts to unify the fundamental gauge interactions, which fail if only Standard Model particles are included in the calculations, but work well if supersymmetric particles appear at the TeV scale [4]. Another hint of new physics at the TeV scale is provided by the astrophysical evidence for dark matter, which is naturally explained by new weakly-interacting particles weighing less than a TeV [5]. Finally, the muon anomalous magnetic moment [6] provides evanescent suggestions of new physics at the TeV scale.