216,877 research outputs found
Generalized Gauge Theories and Weinberg-Salam Model with Dirac-K\"ahler Fermions
We extend previously proposed generalized gauge theory formulation of
Chern-Simons type and topological Yang-Mills type actions into Yang-Mills type
actions. We formulate gauge fields and Dirac-K\"ahler matter fermions by all
degrees of differential forms. The simplest version of the model which includes
only zero and one form gauge fields accommodated with the graded Lie algebra of
supergroup leads Weinberg-Salam model. Thus the Weinberg-Salam model
formulated by noncommutative geometry is a particular example of the present
formulation.Comment: 33 pages, LaTe
Pati-Salam explanations of the B-meson anomalies
We provide a combined explanation of the increasingly tantalizing -meson
anomalies, both in and , in the Pati-Salam model
with minimal matter content. This well-known model, based on the gauge group
, naturally contains a variety of
scalar leptoquarks with related and restricted couplings. In particular we show
that the seesaw-motivated scalar leptoquark within the representation
and its right-handed parity partner can solve both anomalies while making testable predictions for related
observables such as and . The solution of the
anomaly alone can be related to a type-II seesaw neutrino mass
structure. Explaining also requires the existence of a light
right-handed neutrino, which constrains the UV structure of the model.Comment: 26 pages, includes discussion of RGEs; to appear in JHE
A microeconomic system-wide approach to the estimation of the demand for money
Money supply ; Monetary theory
On the q
Recently Al-Salam and Verma discussed two polynomial sets {Zn(α)(x,k|q)} and {Yn(α)(x,k|q)} which are biorthogonal on (0,∞) with respect to a continuous or discrete distribution function. For the polynomials Yn(α)(x,k|q) the operational formula is derived
Exophobic Quasi-Realistic Heterotic String Vacua
We demonstrate the existence of heterotic-string vacua that are free of
massless exotic fields. The need to break the non-Abelian GUT symmetries in k=1
heterotic-string models by Wilson lines, while preserving the GUT embedding of
the weak-hypercharge and the GUT prediction sin^2\theta_w(M(GUT))=3/8,
necessarily implies that the models contain states with fractional electric
charge. Such states are severely restricted by observations, and must be
confined or sufficiently massive and diluted. We construct the first
quasi-realistic heterotic-string models in which the exotic states do not
appear in the massless spectrum, and only exist, as they must, in the massive
spectrum. The SO(10) GUT symmetry is broken to the Pati-Salam subgroup. Our PS
heterotic-string models contain adequate Higgs representations to break the GUT
and electroweak symmetry, as well as colour Higgs triplets that can be used for
the missing partner mechanism. By statistically sampling the space of
Pati-Salam vacua we demonstrate the abundance of quasi--realistic three
generation models that are completely free of massless exotics, rendering it
plausible that obtaining realistic Yukawa couplings may be possible in this
space of models.Comment: 14 pages. Standard LaTex. 1 figure. 2 tables. Typos correcte
Graviton Propagation in an Asymmetric Warped Background: Lorentz Violation and the Null Energy Condition
The graviton propagation in an asymmetric background is studied. The
background is a configuration in the six-dimensional Salam-Sezgin model, in
which a 3-form H-field turned on [JHEP 0910(2009)086]. The compact dimensions
form a cylindrical space with branes as boundaries. The background gets
asymmetry due to the H-field and violates the Lorentz symmetry. We derive the
graviton equation in this background and show that it gets massless mode
traveling with superluminal speed. A tower of K-K modes exists with a mass gap.
On the other hand, it is known that breaking the Lorentz symmetry on an
asymmetric background is constrained by the null energy condition. This no-go
theorem doesn't work well in six-dimensional space-times and by this model we
provide a counterexample for which the null energy condition is satisfied while
the Lorentz symmetry is gravitationally violated.Comment: 20 pages, 1 figure. v2: published version, more phenomenological
discussions added, references added, numerical error fixe
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