Related papers: Fuzzy Mass Relations in the Standard Model
Whether the Standard Model electroweak vacuum is stable, metastable or unstable depends crucially on the top mass (and, to a lesser extent, on other measurable quantities). These topics are reviewed and updated by taking into account the…
We consider the Minimal Supersymmetric Standard Model (MSSM) without imposing relations on the superpartner masses that arise in grand unified theories. Given an arbitrary pattern of superpartner masses (consistent with experimental…
Models for what may lie behind the Standard Model often require non-perturbative calculations in strongly coupled field theory. This creates opportunities for lattice methods, to obtain quantities of phenomenological interest as well as to…
We motivate and explore the possibility that extra SU(N) gauge groups may exist independently of the Standard Model groups, yet not be subgroups of some grand unified group. We study the running of the coupling constants as a potential…
Renormalisation group analysis with the present measurements of the top quark mass $m_t = 172.69\pm 0.30$ GeV indicates that the Standard Model (SM) Higgs potential becomes unstable at energy scales $\sim 10^{10}$ GeV. This may be…
We study the renormalization group evolution of the Higgs quartic coupling $\lambda_{H}$ and the Higgs mass $m_{H}$ in the Standard Model. The one loop equation for $\lambda_{H}$ is non linear and it is of the Riccati type which we…
The initial data on the production and decay of the Higgs boson reported significant deviations from the Standard Model (SM) expectations, prompting much speculation about its couplings to the other particles. Although the latest data has…
This is a slightly extended version of the talk delivered at the Topical Workshop ``Non perturbative aspects of chiral gauge theories'', Accademia Nazionale dei Lincei, Roma, 9-11 March, 1992. Abstract: The Higgs mass in the minimal…
The status of coupling constant unification -- assuming the validity of the standard model or of its minimal supersymmetric extension at high energies -- and of relations between various Yukawa couplings (assuming the supersymmetri…
The issue of gauge unification in the (non-supersymmetric) Standard Model is reinvestigated. It is found that with just an additional fourth generation of quarks and leptons, $SU(3) \otimes SU(2) \otimes U(1)$ gauge couplings converge to a…
We show that the requirements of renormalizability and physical consistency imposed on perturbative interactions of massive vector mesons fix the theory essentially uniquely. In particular physical consistency demands the presence of at…
We show that the Standard Model vacuum can be stabilized if all particle propagators are non-minimally coupled to gravity. This is due to a Higgs-background dependent redefinition of the Standard Model fields: in terms of canonical…
The renormalization group flows of the coupling constants for the gauged U(N) vector model, with N_f massless fermions in the defining representation, are studied in the large N limit, to all orders in the scalar coupling lambda, leading…
We search for alternatives to the trivial $\phi^4$ field theory by including arbitrary powers of the self-coupling. Such theories are renormalizable when the natural cutoff dependencies of the coupling constants are taken into account. We…
We discuss the role that Higgs coupling measurements can play in differentiating supersymmetric extensions of the Standard Model. Fitting current LHC data to the Higgs couplings, we find that the likelihood fit shows a preference in the…
In the Minimal Supersymmetric Standard Model (MSSM), a Higgs boson mass of 125 GeV can be obtained with moderately heavy scalar top superpartners provided they are highly mixed. The source of this mixing, a soft trilinear stop-stop-Higgs…
Composite Higgs Models explore the possibility that the Higgs boson is an excitation of a new strongly interacting sector giving rise to electro-weak symmetry breaking. After describing how this new sector can be embedded into the Standard…
The considerable part of the parameter space in the MSSM corresponding to the infrared quasi fixed point scenario is excluded by LEP II bounds on the lightest Higgs boson mass. In the NMSSM the mass of the lightest Higgs boson reaches its…
We have investigated the renormalization group running of the pole mass in the multi-Higgs theory in two different types of the gauge fixing conditions. It turns out that the pole mass when expressed in terms of the Lagrangian parameters,…
We explore the possibility of achieving one--step unification of the standard model coupling constants within non supersymmetric and supersymmetric gauge models, which at low energies have only the standard particle content. The constraints…