Triviality and Vacuum Stability Bounds on the Higgs Boson Mass beyond the Standard Model

The triviality and vacuum stability bounds on the Higgs-boson mass were revisited in presence of weakly-coupled new interactions parameterized in a model-independent way by effective operators of dimension 6. It was shown that for the scale of new physics in the region Lambda=.5-50 TeV the Standard Model triviality upper bound remains unmodified whereas it is natural to expect that the lower bound derived from the requirement of vacuum stability is increased by 40-60 GeV depending on the scale Lambda and strength of coefficients of effective operators. It turns out that if the Higgs-boson mass is close to its lower LEP limit then the upper bound on the scale of new physics that follows from the vacuum stability requirement would be decreased dramatically even for modest values of coefficients of effective operators implying new physics already at the scale of a few TeV.