The Standard Model on Non-Commutative Space-Time

We consider the Standard Model on a non-commutative space and expand the action in the non-commutativity parameter theta. No new particles are introduced, the structure group is SU(3) x SU(2) x U(1). We derive the leading order action. At zeroth order the action coincides with the ordinary Standard Model. At leading order in theta we find new vertices which are absent in the Standard Model on commutative space-time. The most striking features are couplings between quarks, gluons and electroweak bosons and many new vertices in the charged and neutral currents. We find that parity is violated in non-commutative QCD. The Higgs mechanism can be applied. QED is not deformed in the minimal version of the NCSM to the order considered.Comment: 28 pages, v3: typos corrected, new appendix on alternative kinetic terms for gauge bosons; v4: typos correcte

Bicovariant Quantum Algebras and Quantum Lie Algebras

A bicovariant calculus of differential operators on a quantum group is constructed in a natural way, using invariant maps from \fun\ to \uqg\ , given by elements of the pure braid group. These operators --- the `reflection matrix' $Y \equiv L^+ SL^-$ being a special case --- generate algebras that linearly close under adjoint actions, i.e. they form generalized Lie algebras. We establish the connection between the Hopf algebra formulation of the calculus and a formulation in compact matrix form which is quite powerful for actual computations and as applications we find the quantum determinant and an orthogonality relation for $Y$ in $SO_q(N)$.Comment: 38 page

An axially-symmetric Newtonian Boson Star

A new solution to the coupled gravitational and scalar field equations for a condensed boson field is found in Newtonian approximation. The solution is axially symmetric, but not spherically symmetric. For N particles the mass of the object is given by $M = Nm - 0.02298 N^3 G_N^2 m^5$, to be compared with $M = Nm - 0.05426 N^3 G_N^2 m^5$ for the spherically symmetric case.Comment: 4 pages, figures available on reques

The Standard Model on Non-Commutative Space-Time: Electroweak Currents and Higgs Sector

In this article we review the electroweak charged and neutral currents in the Non-Commutative Standard Model (NCSM) and compute the Higgs and Yukawa parts of the NCSM action. With the aim to make the NCSM accessible to phenomenological considerations, all relevant expressions are given in terms of physical fields and Feynman rules are provided.Comment: 33 pages, axodraw.sty; shortened, comments and references added, version to appear in EPJ

Road Dust Correlated with Decreased Reproduction of the Endangered Utah Shrub Hesperidanthus suffrutescens

Roads associated with energy development have fragmented much of the Uinta Basin, the Colorado Plateau in general, and other areas of western North America. Beyond reducing available habitat, spreading exotic species, and creating barriers to dispersal, unpaved roads also increase dust loads on plants and pollinators, which may reduce plant growth and reproduction. We studied the effects of an unpaved road on reproduction of an endangered Utah endemic shrub. We measured the size and reproductive output of 156 plants and the dust deposition in plots at increasing distances from the road. We also hand outcrossed 240 flowers from 80 plants to help determine if any reduced reproduction was due to pre- or postpollination mechanisms. Additionally, we experimentally dusted 3 leaves on 30 plants (n = 90) and measured stomatal conductance pre-dust and post-dust. We also dusted 3 flowers on 10 plants (n = 30) prior to hand pollination and measured fruit set. Generalized linear mixed models were used to examine the relationship between reproduction and dust deposition. When controlling for plant size and distance from the road, fruit set was negatively correlated with increasing levels of dust deposition (F1, 15 = 5.26, P = 0.036). The number of seeds per plant, mean plant seed weight, and the proportion of hand-pollinated flowers that set fruit were also negatively correlated with dust, although not significantly. Dusting significantly reduced stomatal conductance (F1, 58 = 87.56, P \u3c 0.001). Eighty percent of hand pollinated flowers (24 of 30) set fruit after dusting. These results demonstrate that road dust reduces H. suffrutescens reproduction, although the mechanisms are not clear. Although dust negatively affected physiological processes, hand-pollination results suggest that dust might be disrupting pollination. This study documents the effects of road dust on the reproduction of an endangered shrub in Utah\u27s Uinta Basin and highlights the need for further research into the effects of roads and dust on nearby plants

On Quantum Groups in the Hubbard Model with Phonons

The correct Hamiltonian for an extended Hubbard model with quantum group symmetry as introduced by A. Montorsi and M. Rasetti is derived for a D-dimensional lattice. It is shown that the superconducting SUq(2) holds as a true quantum symmetry only for D = 1 and that terms of higher order in the fermionic operators in addition to phonons are required for a quantum symmetric hamiltonian. The condition for quantum symmetry is "half filling" and there is no local electron-phonon coupling. A discussion of Quantum symmetries in general is given in a formalism that should be readily accessible to non Hopf-algebraists.Comment: latex, 17 page