Related papers: Warped Unification, Proton Stability and Dark Matt…

We address the problem of baryon number violation in Randall-Sundrum backgrounds and provide a solution leading to a stable light Kaluza--Klein fermion in warped GUT. This adds to the list of dark matter candidates which stability can…

In the past year, a new non-supersymmetric framework for electroweak symmetry breaking (with or without Higgs) involving SU(2)_L * SU(2)_R * U(1)_{B-L} in higher dimensional warped geometry has been suggested. In this work, we embed this…

We consider a scenario where a supersymmetric model has multiple dark matter particles. Adding a U(1)' gauge symmetry is a well-motivated extension of the Minimal Supersymmetric Standard Model (MSSM). It can cure the problems of the MSSM…

A review of baryon and lepton conservation in supersymmetric grand unified theories is given. Proton stability is discussed in the minimal SU(5) supergravity grand unification and in several non-minimal extensions such as the $SU(3)^3$,…

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…

We analyze a recently proposed extension of the Standard Model based on the SU(4) x SU(2)_L x U(1)_X gauge group, in which baryon number is interpreted as the fourth color and dark matter emerges as a neutral partner of the ordinary quarks…

The first part of this talk presents the general complexion of baryon and lepton number non-conservation that may arise in the context of quark-lepton unification. The second part presents the status of grand unification with and without…

Generic extensions of the Standard Model that respect baryon and lepton numbers have accidentally stable particles. Typical examples are the lightest exotic neutral fermion, or "neutralino", and fields with non-trivial lepton and baryon…

In generic models for grand unified theories(GUT), various types of baryon number violating processes are expected when quarks and leptons propagate in the background of GUT strings. On the other hand, in models with large extra dimensions,…

We present a new grand unification paradigm, where gauge couplings do not need to be equal at any given scale, instead they run towards the same fixed point in the deep ultraviolet. We provide a concrete example based on SU(5) with a…

We consider a setup where R-parity is violated in the framework of split supersymmetry. The out-of-equilibrium decays of heavy squarks successfully lead to the generation of a baryon asymmetry. We restrict the R-parity violating couplings…

The Minimal Supersymmetric Standard Model (MSSM) with conserved R-parity suffers from several fine-tuning problems, e.g. the mu-problem and the problem of proton decay through higher dimension operators. Both of these problems can be…

Supersymmetry is one of the best motivated new physics scenarios. To build a realistic supersymmetric standard model, however, a companion symmetry is necessary to address various issues. While R-parity is a popular candidate that can…

We propose a mechanism for hiding the primordial baryon asymmetry from interactions that could wash it out. It requires the introduction of a baryon number carrying singlet which is in equilibrium in the early universe and shares any…

Within supersymmetric SU(5) GUT we suggest mechanisms for suppression of baryon number violating dimension five and six operators. The mechanism is based on the idea of split multiplets (i.e. quarks and leptons are not coming from a single…

In models with a low quantum gravity scale, one might expect that all operators consistent with gauge symmetries are present in the low-energy effective theory. If this is the case, some mechanism must be present to adequately suppress…

We consider a model in which dark matter is a composite baryon of a dark sector governed by $SU(3)$ gauge theory, with vector-like quarks also charged under $U(1)_Y$. The model provides simple answer to the dark matter stability problem: it…

The Standard Model may be included within a supersymmetric theory, postulating new sparticles that differ by half-a-unit of spin from their standard model partners, and by a new quantum number called R-parity. The lightest one, usually a…

Supersymmetry solves the gauge hierarchy problem of the Standard Model if the masses of supersymmetric partners of the SM particles are close to the weak scale. In this thesis, we argue that the supersymmetric Standard Model, while avoiding…

We study the stability of Kaluza-Klein (KK) modes in five-dimensional N=1 supersymmetric QCD compactified on S^1 using the D3-brane probe realization. We find a phenomenon in which the quark KK mode with the KK number n=1 decays while other…