相关论文: Peccei-Quinn symmetry from a hidden gauge group st…
We propose a grand unified model in five dimensions that addresses the strong CP problem. In this framework, the boundary conditions that break the unified gauge group into the Standard Model gauge group simultaneously explain the mass…
Solutions to the $\mu$ problem in supersymmetry based on the Kim-Nilles mechanism naturally feature a Dine-Fischler-Srednicki-Zhitnitsky (DFSZ) axion with decay constant of order the geometric mean of the Planck and TeV scales, consistent…
The breakdown of E_6 within the supersymmetric (SUSY) Grand Unified Theories (GUTs) can result in SUSY extensions of the standard model (SM) based on the SM gauge group together with extra U(1) gauge symmetry under which right-handed…
We suggest a new mechanism for naturally suppressing dimension five baryon number violating in supersymmetric SU(5+N) (N=0, 1,...) GUTs. The mechanism is realized through suppression of qqT type couplings, and is implemented by introducing…
We discuss the anomalous U(1) gauge symmetry as a mechanism of generating the grand-unification scale. We conclude that unification to a simple group cannot be realized unless some parameters are ``tuned'', and that models with product…
To enforce the conservation of baryon number B and not lepton number L in supersymmetry, a new U(1)_X gauge symmetry is recommended. An example is offered with new particles interacting under U(1)_X which are good candidates for the dark…
The baryon asymmetry of the universe can be explained by the out-of-equilibrium decays of heavy right-handed neutrinos. We analyse this mechanism in the framework of a supersymmetric extension of the Standard Model and show that lepton…
Krauss and Wilczek have shown that an unbroken discrete gauge symmetry is respected by gravitationally mediated processes. This has led to a search for such a symmetry compatible with the standard model or MSSM that would protect protons…
Gravitational effects are known to violate global symmetries, threatening the Peccei-Quinn (PQ) solution to the strong CP problem. Ultraviolet completions featuring a gauged $U(1)$ symmetry, where $U(1)_{\rm PQ}$ arises as an accidental…
We demonstrate the formation of quasi-stable localized scalar configurations in spontaneously symmetry breaking U(1) model by 3+1-dimensional classical lattice simulations. Such configurations are called PQ-balls, as the primary motivation…
Invoking the Peccei-Quinn (PQ) solution to the strong CP problem substitutes the puzzle of why $\theta_{qcd}$ is so small with the puzzle of why the PQ symmetry is of such high quality. Cosmological and astrophysical considerations raise…
We construct the supersymmetric version of a model based on the gauge group SU(3)_c X SU(3)_L X U(1). We discuss the mechanism of baryon number violation which induces nucleon decay, and derive bounds on the relevant couplings.
We show that in a self-consistent preon model, where Standard Model quarks and leptons are three-body composites confined at a metacolor scale Lambda_cr ~ 10^14 GeV, both leptoquarks and the Standard Model gauge group SU(3)_c x SU(2)_L x…
We show how the fields and particles of the standard model can be naturally realized in noncommutative gauge theory. Starting with a Yang-Mills matrix model in more than 4 dimensions, a SU(n) gauge theory on a Moyal-Weyl space arises with…
We investigate the prospects of an extra global symmetry, added to the Standard Model in the context of baryogenesis. The $PQ$ symmetry is studied as an example. We show that the hadronic axion provides a protection of the B-asymmetry even…
We present a composite model of quarks with `effective supersymmetry'. The model is based on the gauge group $(SU(2)_S \times SU(2)_M) \times (SU(2)_U \times SU(2)_C \times SU(2)_T) \times SU(5)_{SM}$, where $SU(5)_{SM}$ is the standard…
It was recently suggested that the reported anomalies in $R_b$ and $R_c$ can be interpreted as the effect of a heavy vector boson that couples to quarks and is universally decoupled from leptons. We examine how an extra gauge boson with…
The baryon asymmetry of the universe can be explained by the out-of-equilibrium decays of heavy right-handed neutrinos. We analyse this mechanism in the framework of a supersymmetric extension of the Standard Model and show that lepton…
The smallness of the quark and lepton parameters and the hierarchy between them could be the result of selection rules due to a horizontal symmetry broken by a small parameter. The same selection rules apply to baryon number violating…
We present a 5D axion-neutrino model that explains the Standard Model fermion mass hierarchy and flavor structure, while simultaneously generating a high-quality axion. The axion and right-handed neutrinos transform under a 5D Peccei-Quinn…