If the Higgs mass m(H), is as low as suggested by present experimental information, the Standard Model ground state might not be absolutely stable. We present a detailed analysis of the lower bounds on mH imposed by the requirement that the electroweak vacuum be sufficiently long-lived. We perform a complete one-loop calculation of the tunnelling probability at zero temperature, and we improve it by means of two-loop renormalization-group equations. We find that, for m(H) = 115 GeV, the Higgs potential develops an instability below the Planck scale for mt > (166 +/- 2) Gev, but the electroweak vacuum is sufficiently long-lived for m(t) < (175 +/- 2) GeV. (C) 2001 Elsevier Science B.V. All rights reserved.
On the metastability of the Standard Model vacuum
STRUMIA, ALESSANDRO
2001-01-01
Abstract
If the Higgs mass m(H), is as low as suggested by present experimental information, the Standard Model ground state might not be absolutely stable. We present a detailed analysis of the lower bounds on mH imposed by the requirement that the electroweak vacuum be sufficiently long-lived. We perform a complete one-loop calculation of the tunnelling probability at zero temperature, and we improve it by means of two-loop renormalization-group equations. We find that, for m(H) = 115 GeV, the Higgs potential develops an instability below the Planck scale for mt > (166 +/- 2) Gev, but the electroweak vacuum is sufficiently long-lived for m(t) < (175 +/- 2) GeV. (C) 2001 Elsevier Science B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
