9,894 research outputs found
The SCUBA Local Universe Galaxy Survey
The SCUBA local universe galaxy survey is the first systematic survey of the
local universe at submillimetre wavelengths. We have observed ~200 galaxies
from the IRAS bright galaxy catalogue and the CfA optical redshift survey. The
IRAS sample showed that our estimate of the luminosity function was potentially
biased if a cold population of galaxies existed which would not have appeared
in the IRAS BGS but would have been detected in a SCUBA blind survey. Here we
present preliminary results from the optically selected sample which suggest
that this is indeed the case.Comment: 2 pages, 2 figs, proceedings from Euro-conference on galaxy evolution
held in La Reunion, 200
Symmetry Breaking in the Schr\"odinger Representation for Chern-Simons Theories
This paper discusses the phenomenon of spontaneous symmetry breaking in the
Schr\"odinger representation formulation of quantum field theory. The analysis
is presented for three-dimensional space-time abelian gauge theories with
either Maxwell, Maxwell-Chern-Simons, or pure Chern-Simons terms as the gauge
field contribution to the action, each of which leads to a different form of
mass generation for the gauge fields.Comment: 16pp, LaTeX , UCONN-94-
Quantum Group Covariance and the Braided Structure of Deformed Oscillators
The connection between braided Hopf algebra structure and the quantum group
covariance of deformed oscillators is constructed explicitly. In this context
we provide deformations of the Hopf algebra of functions on SU(1,1). Quantum
subgroups and their representations are also discussed.Comment: 12 pages, to be published in JM
A Gauge-Gravity Relation in the One-loop Effective Action
We identify an unusual new gauge-gravity relation: the one-loop effective
action for a massive spinor in 2n dimensional AdS space is expressed in terms
of precisely the same function [a certain multiple gamma function] as the
one-loop effective action for a massive charged scalar in 4n dimensions in a
maximally symmetric background electromagnetic field [one for which the
eigenvalues of F_{\mu\nu} are maximally degenerate, corresponding in 4
dimensions to a self-dual field, equivalently to a field of definite helicity],
subject to the identification F^2 \Lambda, where \Lambda is the
gravitational curvature. Since these effective actions generate the low energy
limit of all one-loop multi-leg graviton or gauge amplitudes, this implies a
nontrivial gauge-gravity relation at the non-perturbative level and at the
amplitude level.Comment: 6 page
Determining military expenditures: arms races and spill-over effects in cross-section and panel data
This paper considers the determinants of military spending, building on an emerging literature that estimates military expenditure demand functions in cross-section and panel data, incorporating ‘arms-race’ type effects. It updates Dunne and Perlo-Freeman (2003b) using the SIPRI military expenditure database for the period 1988-2003, finding broadly similar results. It also shows differences in results across panel methods, particularly the within and between estimates and illustrates the importance of recognising and modelling dynamic processes within panel data. Heterogeneity is also found to be an important issue and when countries are broken up into groups on the basis of per capita income there is no obvious systematic pattern in the results. This is seen to imply that the demand for military spending, even between two mutually hostile powers, may depend on the whole nature of the relationship between them (and other countries and events in the region), and not simply Richardsonian action-reaction patterns
Braided Oscillators
The braided Hopf algebra structure of the generalized oscillator is
investigated. Using the solutions two types of braided Fibonacci oscillators
are introduced. This leads to two types of braided Biedenharn-Macfarlane
oscillators.Comment: 12 pages, latex, some references added, published versio
Complex Saddles in Two-dimensional Gauge Theory
We study numerically the saddle point structure of two-dimensional (2D)
lattice gauge theory, represented by the Gross-Witten-Wadia unitary matrix
model. The saddle points are in general complex-valued, even though the
original integration variables and action are real. We confirm the
trans-series/instanton gas structure in the weak-coupling phase, and identify a
new complex-saddle interpretation of non-perturbative effects in the
strong-coupling phase. In both phases, eigenvalue tunneling refers to
eigenvalues moving off the real interval, into the complex plane, and the
weak-to-strong coupling phase transition is driven by saddle condensation.Comment: 4+4 pages RevTeX, 9 figures; v2: version published in PR
Numerical Investigation of Monopole Chains
We present numerical results for chains of SU(2) BPS monopoles constructed
from Nahm data. The long chain limit reveals an asymmetric behavior transverse
to the periodic direction, with the asymmetry becoming more pronounced at
shorter separations. This analysis is motivated by a search for semiclassical
finite temperature instantons in the 3D SU(2) Georgi-Glashow model, but it
appears that in the periodic limit the instanton chains either have
logarithmically divergent action or wash themselves out.Comment: 14 pages, 6 figures; v2 minor changes, published versio
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