Related papers: Is CP a Gauge Symmetry?
We consider heterotic string backgrounds in four-dimensional Minkowski space, where N=1 supersymmetry is spontaneously broken at a low scale m_{3/2} by a stringy Scherk-Schwarz mechanism. We review how the effective gauge couplings at…
We propose an alternative to the axion mechanism for addressing the charge parity (CP) problem in quantum chromodynamics (QCD). Our approach involves imposing CP as an inherent symmetry of the Lagrangian, which is then spontaneously broken.…
The axion solution to the strong CP problem makes use of a global Peccei-Quinn U(1) symmetry which is susceptible to violations from quantum gravitational effects. We show how discrete gauge symmetries can protect the axion from such…
We propose a three-zero texture for the down-quark mass matrix within a $SU(5)$ GUT-inspired Standard Model, enforced by a non-invertible selection rule originating from $\mathbb{Z}_2$ gauging of $\mathbb{Z}_N$ symmetries. Assuming CP…
We examine the possibility that the strong CP problem is solved by string-theoretic axions in strong-coupling limit of the E_8 x E_8 heterotic string theory (M-theory). We first discuss some generic features of gauge kinetic functions in…
Spontaneous CP--violation in the minimal supersymmetric standard model with a gauge singlet and a cubic superpotential is examined. Although the tree--level Higgs potential conserves CP, it is shown that with the inclusion of the one--loop…
We investigate the free, massless Dirac equation $D\psi = 0$ on a higher-dimensional manifold $M_4 \times K$ equipped with a submersion metric. These background metrics generalize the Kaluza ansatz. They encode 4D massive gauge fields and…
We discuss CP-violation in a model with a real and a complex isospin triplet Higgs fields without introducing any symmetries except for the electroweak gauge symmetry. This corresponds to the minimal extension of the Higgs sector with the…
It has been shown that QED in (1+4)-dimensional space-time, with the fifth dimension compactified on a circle, leads to CP violation (CPV). Depending on fermionic boundary conditions, CPV may be either explicit (through the Scherk--Schwarz…
We propose a new solution to the strong-CP problem. It involves the existence of an unbroken gauged $U(1)_X$ symmetry whose gauge boson gets a Stuckelberg mass term by combining with a pseudoscalar field $\eta (x)$. The latter has…
We study the CP phases of the soft supersymmetry breaking terms in string-inspired models with non-universal trilinear couplings. We show that such non-universality plays an important role on all CP violating processes. In particular these…
Main objective of the present dissertation is the investigation for all the possible low energy models which emerge in four dimensions by the dimensional reduction of a gauge theory over multiple connected coset spaces. The higher…
CP violation in the SM is naturally implemented as a small imaginary perturbation to real Yukawa couplings. For example, a large CP asymmetry in B_d decays can arise if the imaginary parts of quark mass matrices are of order 10^(-3)m_t,b or…
We consider symmetry breaking of arbitrary gauge groups on a six-dimensional space-time which consists of a four-dimensional Minkowski space-time $M^4$ and a two-dimensional sphere $S^2$. We expand the gauge fields in the presence of a…
Symmetry breaking induced by untwisted fermions in QED in a nonsimply connected spacetime with topology $S^{1}\times R^{3}$ is investigated. It is found that the discrete CPT symmetry of the theory is spontaneously broken by the appearance…
We discuss CP violation in supersymmetric theories and show that CP phenomena can act as a probe of their origins, i.e., compactification and spontaneous supersymmetry breaking. CP violation as a probe of the flavor structure of…
We investigate several problems in relativity and particle physics where symmetries play a central role; in all cases geometric properties of Lie groups and their quotients are related to physical effects. The first part is concerned with…
We propose a mechanism for relaxing a gauge theory CP violating phase in discrete steps to very small values. The idea is that the CP violating phase includes the magnetic dual of a $4$-form flux which can discharge by the nucleation of…
We analyse the general constraints on unified gauge models with spontaneous CP breaking that satisfy the conditions that (i) CP violation in the quark sector is described by a realistic complex CKM matrix, and (ii) there is no significant…
Extended Higgs sectors offer rich opportunities for various forms of CP-violation. Here, we describe a new form of CP-conservation and discuss its consequences. We give a concrete example of a three-Higgs-doublet model dubbed CP4-3HDM with…