Related papers: Gauge Coupling Unification with Hidden Photon, and…
We show that in the framework of grand unified theory (GUT) with anomalous $U(1)_A$ gauge symmetry, the success of the gauge coupling unification in the minimal SU(5) GUT is naturally explained, even if the mass spectrum of superheavy…
WIMP dark matter and gauge coupling unification are considered in an R-parity violating MSSM with vector-like matter. Dark matter is contained in an additional vector-like SU(2)$_L$ doublet which possesses a new U(1) gauge symmetry. The…
Gauge coupling unification and the success of TeV-scale weakly interacting dark matter are usually taken as evidence of low energy supersymmetry (SUSY). However, if we assume that the tuning of the higgs can be explained in some unnatural…
We show that the axion coupling to photons can be enhanced in simple models with a single Peccei-Quinn field, if the gauge coupling unification is realized by a large kinetic mixing $\chi = {\cal O}(0.1)$ between hypercharge and unbroken…
The stability of dark matter is naturally explained if there is an additional U(1) symmetry which is spontaneously broken to a discrete symmetry at a high-energy scale. Such a framework is realized in the context of the SO(10) grand…
A constraint on masses of superheavy gauge and Higgs multiplets at the grand unification (GUT) scale is obtained from the gauge coupling unification in the case of high-scale supersymmetry. We found that all of the particles may lie around…
We study gauge coupling unification in supersymmetric $E_6$ models where an additional $\mathrm{U}(1)'$ gauge symmetry is broken near the TeV scale and a number of exotic matter fields from the $\bm{27}$ representations have…
We investigate the possibility of gauge coupling unification in various radiative neutrino mass models, which generate neutrino masses at one- and/or two-loop level. Renormalization group running of gauge couplings is performed analytically…
We study a new mechanism for the production of dark matter in the universe which does not rely on thermal equilibrium. Dark matter is populated from the thermal bath subsequent to inflationary reheating via a massive mediator whose mass is…
We explore gauge coupling unification and dark matter in high scale supersymmetry where the scale of supersymmetry breaking is much above the weak scale. The gauge couplings unify as precisely as in low energy supersymmetry if the…
Higher dimensional grand unified theories, with gauge symmetry breaking by orbifold compactification, possess SU(5) breaking at fixed points, and do not automatically lead to tree-level gauge coupling unification. A new framework is…
Unlike minimal SU(5), SO(10) provides a straightforward path towards gauge coupling unification by modifying the renormalization group evolution of the gauge couplings above some intermediate scale which may also be related to the seesaw…
The logarithmic running of the gauge couplings alpha_1, alpha_2 and alpha_3, indicates that they may unify at some scale M_GUT ~ 10^16. This is often taken to imply that the standard model gauge group is embedded into some larger simple…
In the absence of low energy supersymmetry, we show that (a) the dark matter particle alone at the TeV scale can improve gauge coupling unification, raising the unification scale up to the lower bound imposed by proton decay, and (b) the…
Motivated by gauge coupling unification and dark matter, we present an extension to the Standard Model where both are achieved by adding an extra new matter multiplet. Such considerations lead to a Grand Unified Theory with very heavy…
We consider dark matter in a minimal extension of the Standard Model (SM) which breaks electroweak symmetry dynamically and leads to a complete unification of the SM and technicolor coupling constants. The unification scale is determined to…
The possibility of achieving a gauge coupling grand unification by increasing the QCD degrees of freedom at higher energies is investigated. When confronted with precision low-energy data, the generic weak-mixing angle relation…
We make a detailed analysis of gauge coupling unification in supersymmetry. When the Standard Model gauge group is embedded in a Grand Unified Theory, new particles often appear below the GUT scale in order to predict the right…
Unparticle physics from a hidden conformal sector can alter the evolution of the Standard Model (SM) gauge couplings via TeV scale threshold corrections. We discuss how this may lead to gauge coupling unification at M_{GUT}\approx 2 \times…
With minimal field content and for an interesting range of the supersymmetric Higgs mixing parameter, 0.5 < tan^2 \beta < 2, the superpartner mass scale, \tilde{m}, is found to be at the intermediate scale, ~ 10^{10 \pm 1} GeV, near where…