Related papers: CP from strings: ideas and problems

The weakly-coupled heterotic string is known to have problems of dilaton/moduli stabilization, supersymmetry breaking (by hidden-sector gaugino condensation), gauge coupling unification (or the Newton's constant), QCD axion, as well as…

We propose a new solution to the strong CP problem based on supersymmetric non-renormalization theorems. CP is broken spontaneously and it's breaking is communicated to the MSSM by radiative corrections. The strong CP phase is protected by…

The coupling between Chern-Simons theories and matter sources defined by branes of different dimensionalities is examined. It is shown that the standard coupling to membranes, such as the one found in supergravity or in string theory, does…

We show that, in perturbative string models where the source of CP violation is a complex vacuum expectation value (v.e.v.) for one or more compactification moduli, CP is conserved if a CP transformation acting on the modulus values is an…

In this thesis we study top-condensation models of electroweak symmetry breaking. In particular we investigate a scenario in which the CP symmetry is broken spontaneously due to the same condensates responsible of electroweak symmetry…

We study flavour physics and CP violation in the context of low energy Supersymmetry with non-universal soft mass terms for sfermions. Large deviations from Standard Model predictions are allowed in B-physics, as shown in two explicit…

Quantum field theory has been established on symmetries, but their fundamentality could be limited as practical calculations of physical observations are not based on interacting Lagrangian. The requirement of Lorentz invariance on vacuum…

Possible CP violation in supersymmetric (SUSY) extensions of the Standard Model (SM) is discussed. The consequences of CP violating phases in the gaugino masses, trilinear soft supersymmetry-breaking terms and the `mu' parameter are…

Four-dimensional string theories predict in general the existence of light exotic particles with fractional electric charges. Such particles could escape present observations if they are confined by a gauge group of the "hidden" sector into…

CP violation by soft supersymmetry-breaking terms in orbifold compactifications is investigated. We include the universal part of the moduli-dependent threshold corrections in the construction of the non-perturbative effective potential due…

We explore the possibility of spontaneous CP violation within the Next to Minimal Supersymmetric Standard Model. In the most general form of the model, without a discrete $Z_3$ symmetry, we find that even at tree level spontaneous CP…

A review about some recent studies on the determination of the CP-violating complex parameters in supersymmetry at an e^+ e^- linear collider is presented. CP-even observables, like masses, cross sections and branching ratios, can have a…

String theoretic axion is a prime candidate for the QCD axion solving the strong CP problem. For a successful realization of the QCD axion in string theory, one needs to stabilize moduli including the scalar partner (saxion) of the QCD…

This article is devoted to an overview of superstring perturbation theory from the point of view of super Riemann surfaces. We aim to elucidate some of the subtleties of superstring perturbation that caused difficulty in the early…

If CP violation in the decays of neutral kaons is due to phases in the weak couplings of quarks, as encoded in the Cabibbo-Kobayashi-Maskawa (CKM) matrix, there are many other experimental consequences. Notable among these are CP-violating…

Supersymmetric theories with a $U(1)_R$ symmetry have Dirac gauginos, solve the supersymmetric flavor and CP problems, and have distinctive collider signatures. However when supergravity is included, the $U(1)_R$ must be broken, adding…

I discuss several aspects of strings as unified theories. After recalling the difficulties of the simplest supersymmetric grand unification schemes I emphasize the distinct features of string unification. An important role in constraining…

We examine a class of Froggatt-Nielsen models with an anomalous U(1) as the flavor dependent symmetry. Anomaly cancellation and unbroken supersymmetry impose constraints on the U(1)_X charges of the fermions and the vacuum expectation…

Supersymmetric extensions of the standard model generically contain additional sources of CP violation. We discuss how at one loop a potentially large CP violating coupling of the lightest Higgs, h^0, to leptons is induced in the minimal…

The strong CP problem remains one of the most important unresolved issues in the Standard Model. Spontaneous CP violation (SCPV) is a promising approach to the problem by assuming that CP is an exact symmetry of the Lagrangian but broken…