12,697 research outputs found
No strong coupling regime in the fermion-Higgs sector of the standard model
We present results for the renormalized quartic self-coupling \lm_R and the
renormalized Yukawa coupling in a fermion-Higgs model with two SU(2)
doublets, indicating that these couplings are not very strong.Comment: 4 pages, 4 postscript figures (appended), ITFA-92-32, HLRZ-92-92,
UCSD/PTH 92-43, Contribution to the Conference Lattice'9
Staggered fermions for chiral gauge theories: Test on a two-dimensional axial-vector model
As a first step towards constructing chiral models on the lattice with
staggered fermions, we study a U(1) model with axial-vector coupling to an
external gauge field in two dimensions. In our approach gauge invariance is
broken, but it is restored in the classical continuum limit. We find that the
continuum divergence relations for the vector and axial-vector currents are
reproduced, up to contact terms, which we determine analytically. The current
divergence relations are also studied numerically for smooth external gauge
fields with topological charge zero. We furthermore investigate the effect of
fluctuating gauge transformations and of gauge configurations with non-trivial
topological charge.Comment: 17 pages, 5 postscript figures (appended), ITFA 93-13, UCSD/PTH 93-1
Process description of SWQN : A simplified hydraulic model
SWQN is a simplified hydraulic model for surface water systems which computes water levels and flows in a network of nodes labelled as ‘volumes’ and segments labelled as ‘connectors’. The user can specify a variety of connectors like open water courses or structures such as weirs, gates, culverts or pumps. Water levels are calculated in the ‘volumes’ driving the one dimensional flows through the ‘connectors’ linking up the ‘volumes’. The assumption is that the flow between two nodes with an open connection in between is linearly dependent on the difference in water level, if necessary augmented with the difference in velocity head, the wetted profile, and a given resistance
Chiral gauge theories on the lattice and restoration of gauge symmetry
We investigate a proposal for the construction of models with chiral fermions
on the lattice using staggered fermions. In this approach the gauge invariance
is broken by the coupling of the staggered fermions to the gauge fields. We aim
at a dynamical restoration of the gauge invariance in the full quantum model.
If the gauge symmetry breaking (SB) is not too severe, this procedure could
lead in the continuum limit to the desired gauge invariant chiral gauge theory.Comment: 3 pages, 2 postscript files appended (uuencoded), contribution to
Lattice'93, ITFA 93-32, UCSD/PTH 93-3
The governance of innovation diffusion – a socio-technical analysis of energy policy
This paper describes a dynamic price mechanism to coordinate electric power generation from micro Combined Heat and Power (micro-CHP) systems in a network of households. It is assumed that the households are prosumers, i.e. both producers and consumers of electricity. The control is done on household level in a completely distributed manner. Avoiding a centralized controller both eases computation complexity and preserves communication structure in the network. Local information is used to decide to turn on or off the micro-CHP, but through price signals between the prosumers the network as a whole operates in a cooperative way
Health Benefits of Urban Agriculture
Health professionals increasingly recognize the value of farm-and garden-scale urban agriculture. Growing food and non-food crops in and near cities contributes to healthy communities by engaging residents in work and recreation that improves individual and public well-being. This article outlines the benefits of urban agriculture with regard to nutrition, food security, exercise, mental health, and social and physical urban environments. Potential risks are reviewed. Practical recommendations for health professionals to increase the positive benefits of urban agriculture are provided
Thermalisation of inhomogeneous quantum scalar fields in 1+1D
Using an improved version of the Hartree approximation, allowing for
ensembles of inhomogeneous configurations, we show in a
theory, that initially the system thermalises with a Bose-Einstein
distribution. For later times and larger couplings we see deviations.Comment: Presented at CAPP 2000, 4 pages including figures, typo's correcte
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