Related papers: Number-Theory Dark Matter
I comment on the proposal that the stability of dark matter may be due to an unbroken Z_2 symmetry contained in the partially broken lepton flavour symmetry group. I remark that (1) there is no Z_2 symmetry apparent in the lepton mass…
The left-right symmetric Pati-Salam model of the unification of quarks and leptons is based on SU(4) and SU(2)xSU(2) groups. These groups are naturally extended to include the classification of families of quarks and leptons. We assume that…
We show that under a new U(1) gauge symmetry, which is non-anomalous in the presence of one ``right-handed neutrino'' per generation and consistent with the standard model Yukawa couplings, the most general fermion charges are determined in…
It is known that two heavy Majorana right-handed neutrinos are sufficient to generate the baryon asymmetry in the present universe. Thus, it is interesting to identify the third right-handed neutrino $N$ with the dark matter. We impose a…
The $SU(3)_c^{}\times SU(2)_L^{} \times U(1)_Y^{}$ standard model is extended by a $U(1)_{B-L}^{}$ gauge symmetry with four right-handed neutrinos. Because of their Yukawa couplings to a Higgs singlet for spontaneously breaking the…
If dark matter is light, it may be due to a seesaw mechanism just as neutrinos are. It is postulated that both originate from the same type of heavy fermion anchors, either singlets or triplets. In the latter case, a shift of the $W$ mass…
Dirac fermions coupled to gauge fields can exhibit the chiral anomaly even on a finite spatial lattice. A careful description of this phenomenon yields new insights into the nature of spin-charge relations and on-site symmetries (symmetries…
We present exact non-perturbative solutions to chiral gauge theories based on the $E_6$ gauge group and several matter fermions in the fundamental $\bf{27}$-dimensional representation. They are obtained when supersymmetric versions are…
Defining chiral lattice gauge theories in the Ginsparg-Wilson formalism is complicated by the so-called fermion measure problem. It has been proven for the abelian theories that smooth well-behaved fermion measure exists if and only if the…
The internal structure of the Standard Model implies a natural $\mathbb{Z}_4 \times \mathbb{Z}_3$ discrete gauge symmetry. Cancellation of the corresponding Dai--Freed anomalies requires the introduction of three right-handed neutrinos and…
The Standard Model has three generations of fermions and although it does not contain any explicit reason for this, the existence of additional generations is now very constrained by experiment. Present measurements are saturating…
We propose two supersymmetric Standard Models (SMs) with decaying and stable dark matter (DM) particles. To explain the SM fermion masses and mixings and have a heavy decay DM particle S, we consider the Froggatt-Nielsen mechanism by…
The existence of an anomalous U(1) symmetry is shown to play a crucial role in the supersymmetric radiative seesaw model for neutrino masses. It explains the smallness of some couplings related to neutrino mass generation in a favorable way…
The paper suggests a left-right mirror symmetric model with the global $U(1)_{B-L}\otimes U(1)_{D}$ symmetries. The model can simultaneously accommodate the standard model, neutrino physics, matter-antimatter asymmetry and cold dark matter.…
A gauge $U(1)$ family symmetry is proposed, spanning the quarks and leptons as well as particles of the dark sector. The breaking of $U(1)$ to $Z_2$ divides the two sectors and generates one-loop radiative masses for the first two families…
We propose an extension of the Standard Model gauge symmetry by the gauge group $U(1)_{T3R}$ in order to address the Yukawa coupling hierarchy between the third generation fermions and the first two generation fermions of the SM. We assume…
In this paper we further elaborate on our recently proposed solution to the cosmological constant problem - Phys. Rev. D82 (2010) 044006. One of the elements of the solution is the chameleonic behaviour of the Einstein frame dilaton: the…
When the classically conformal invariance is imposed on the minimal gauged B-L extended Standard Model (SM), the B-L gauge symmetry is broken by the Coleman-Weinberg mechanism naturally at the TeV scale. Introducing a new Z_2 parity in the…
We consider a U(1)' gauge symmetry acting on three generations of right-handed neutrinos. The U(1)' symmetry is broken at the TeV scale and its remnant discrete symmetry makes one of the right-handed neutrinos stable. As a natural…
The Standard Model gauge symmetry is extended by $U(1)_{B-L}$ which when spontaneously broken leads to residual $\mathbb{Z}_4$ symmetry. $U(1)_{B-L}$ gauge symmetry made anomaly free by introducing exotic SM singlets with corresponding…