Related papers: On sphaleron deformations induced by Yukawa intera…
Here, we provide a simple Hubbard-like model of spin-$1/2$ fermions that gives rise to the SU(2) symmetric Thirring model that is equivalent, in the low-energy limit, to Yang-Mills-Chern-Simons model. First, we identify the regime that…
We find a large class of quantum gauge models with massless fermions where the coupling to the gauge fields is not chirally symmetric and which nevertheless do not suffer from gauge anomalies. To be specific we study two dimensional Abelian…
We investigate the Yukawa model in which $N_f$ fermions are coupled with a scalar field $\phi$ through a Yukawa interaction. The phase diagram is rather well understood. If the fermions are massless, there is a chiral transition at $T_c$:…
We consider N Dirac fermions on a 4-dimensional Euclidean space with a quadratic interaction given by arbitrary external Clifford-valued fields. The divergence of the axial current satisfies on the classical level a relation that is…
In gauge-Higgs unification (GHU), gauge symmetry is dynamically broken by an Aharonov-Bohm (AB) phase, $\theta_H$, in the fifth dimension. We analyze $SU(2)$ GHU with an $SU(2)$ doublet fermion in flat $M^4 \times (S^1/Z_2)$ spacetime and…
We extend the adiabatic regularization method for an expanding universe to include the Yukawa interaction between quantized Dirac fermions and a homogeneous background scalar field. We give explicit expressions for the renormalized…
We study limits of vanishing Yukawa couplings of 4d chiral matter fields in Quantum Gravity, using as a laboratory type IIA orientifolds with D6-branes. In these theories chiral fermions arise at brane intersections, where an infinite tower…
We study superfluidity in a model of massless fermions coupled to a massive scalar field through a Yukawa interaction. Gap equations for a condensate with total spin J=0 are solved in the mean-field approximation. For the Yukawa…
We review the parity anomaly and a duality web in 2+1 dimensions. An odd dimensional non-interacting Dirac fermion theory is not parity invariant at quantum level. We demonstrate the parity anomaly in a three dimensional non-interacting…
We consider the properties of the type II Weyl semimetals at low temperatures basing on the particular tight - binding model. In the presence of electric field directed along the line connecting the Weyl points of opposite chirality the…
We investigate the finite-temperature behavior of the Yukawa model in which $N_{f}$ fermions are coupled with a scalar field $\phi$ in the limit $N_f \to \infty$. Close to the chiral transition the model shows a crossover between mean-field…
We consider SU(2)-equivariant dimensional reduction of Yang-Mills-Dirac theory on manifolds of the form M x CP(1), with emphasis on the effects of non-trivial magnetic flux on CP(1). The reduction of Yang-Mills fields gives a chain of…
Measurement of the Yukawa interaction between the top quark and the Higgs boson should be useful to clarify the mechanism of fermion mass generation. We discuss the impact of non-standard interactions characterized by dimension-six…
We investigate the fermions of the standard model without a Higgs scalar. Instead, we consider a non-local four-quark interaction in the tensor channel which is characterized by a single dimensionless coupling $f$. Quantization leads to a…
Dynamical Chern-Simons gravity (dCS) is a four-dimensional parity-violating extension of general relativity. Current models predict the effect of this extension to be negligible due to large decay constants $f$ close to the scale of grand…
The realisation that the electroweak anomaly can induce significant baryon number violation at high temperature and that the standard models of particle physics and cosmology contain all the ingredients needed for baryogenesis has led to…
We construct renormalizable Standard Model extensions, valid up to the Planck scale, that give a composite Higgs from a new fundamental strong force acting on fermions and scalars. Yukawa interactions of these particles with Standard Model…
Functional Renormalisation Group (FRG) equations are constructed for a simple Yukawa-model with discrete chiral symmetry, including also the effect of a nonzero composite fermion background beyond the conventional scalar condensate. The…
Spontaneously broken Abelian gauge symmetries can explain the fermion mass hierarchies of the minimal supersymmetric standard model. In most cases it is assumed that the $U(1)_H$ symmetry is anomalous. However, non-anomalous models are also…
In the two-Higgs-Doublet model the alignment of the Yukawa flavour matrices of the two scalar doublets guarantees the absence of tree-level flavour-changing neutral couplings. The resulting fermion-scalar interactions are parameterized in…