4,540 research outputs found
One Loop Field Strengths of Charges and Dipoles on a Locally de Sitter Background
We use the one loop vacuum polarization induced by scalar quantum
electrodynamics to compute the electric and magnetic fields of point charges
and magnetic dipoles on a locally de Sitter background. Our results are
consistent with the physical picture of an inflating universe filling with a
vast sea of charged particles as more and more virtual infrared scalar are
ripped out of the vacuum. One consequence is that vacuum polarization quickly
becomes nonperturbatively strong. Our computation employs the Schwinger-Keldysh
effective field equations and is done in flat, conformal coordinates. Results
are also obtained for static coordinates.Comment: 35 pages, no figures, uses LaTeX 2
FRA/ERE PROJECT I-75 RETIREMENT CONFERENCE AND FOCUS GROUPS: RATIONALE AND STATUS REPORT
This paper is a part of a series of reports of the activities conducted under a grant from the Fund for Rural America, U.S. Department of Agriculture. Funds for the three year grant entitled "Enhancing Rural Economies Through Comprehensive Extension, Research & Partnering Approaches Using Multi-County Clusters in Michigan With Application to National Rural Settings" were received by Michigan State University's Department of Agricultural Economics in March, 1998. The major goal of the grant is to increase economic development activity in four clusters of rural counties in Michigan through the utilization of the resources of the Michigan State University Extension Service, Michigan Agricultural Experiment Station, and other resources of Michigan State University. Various local, state, and federal public partners as well as the private sector are to co-sponsor projects. This paper represents the first stages of a continuing project to explore the utilization of retirement community human resources in rural Michigan and to develop Extension programs to meet their needs. Future activities include focus groups, labor supply analysis, a conference, and perhaps a rural academy to be developed by Michigan State University and its partners.Farm Management,
GOVERNMENT SHUTDOWN: A TEST OF MARKET EFFECIENCY
How does the market react to a government shutdown? Can investors earn above normal returns by acting on this type of information? How efficient is the market in reacting to the announcement of this type of event? This event study tests market efficiency theory by analyzing the impact of two recent US Government shutdowns on the risk adjusted stock price returns of a sample of 50 firms. This study used the standard risk adjusted event study methodology found in the finance literature. Evidence confirms the significant and consistent negative reaction of the risk adjusted returns for the two 50 firm samples of government contracting firms up to 30 days before and after the announcements of the 1995 and 2013 government shutdown. Evidence here documents the tremendous loss of market capital in reaction to a failure of the Federal Government policy makers to compromise and produce a timely operating budget
Sensitivity of Helioseismic Measurements of Normal-mode Coupling to Flows and Sound-speed Perturbations
In this article, we derive and compute the sensitivity of measurements of
coupling between normal modes of oscillation in the Sun to underlying flows.
The theory is based on first-Born perturbation theory, and the analysis is
carried out using the formalism described by \citet{lavely92}. Albeit tedious,
we detail the derivation and compute the sensitivity of specific pairs of
coupled normal modes to anomalies in the interior. Indeed, these kernels are
critical for the accurate inference of convective flow amplitudes and
large-scale circulations in the solar interior. We resolve some inconsistencies
in the derivation of \citet{lavely92} and reformulate the fluid-continuity
condition. We also derive and compute sound-speed kernels, paving the way for
inverting for thermal anomalies alongside flows.Comment: 24 pages, 8 Figures; MNRA
Two Loop Scalar Bilinears for Inflationary SQED
We evaluate the one and two loop contributions to the expectation values of
two coincident and gauge invariant scalar bilinears in the theory of massless,
minimally coupled scalar quantum electrodynamics on a locally de Sitter
background. One of these bilinears is the product of two covariantly
differentiated scalars, the other is the product of two undifferentiated
scalars. The computations are done using dimensional regularization and the
Schwinger-Keldysh formalism. Our results are in perfect agreement with the
stochastic predictions at this order.Comment: 43 pages, LaTeX 2epsilon, 5 figures (using axodraw.sty) Version 2 has
updated references and important corrections to Tables 3-5 and to eqns
(139-141), (145-146), (153-155), (158) and (160
A Simple Operator Check of the Effective Fermion Mode Function during Inflation
We present a relatively simple operator formalism which reproduces the
leading infrared logarithm of the one loop quantum gravitational correction to
the fermion mode function on a locally de Sitter background. This rule may
serve as the basis for an eventual stochastic formulation of quantum gravity
during inflation. Such a formalism would not only effect a vast simplification
in obtaining the leading powers of at fixed loop orders, it would also
permit us to sum the series of leading logarithms. A potentially important
point is that our rule does not seem to be consistent with any simple infrared
truncation of the fields. Our analysis also highlights the importance of spin
as a gravitational interaction that persists even when kinetic energy has
redshifted to zero.Comment: 39 pages, no figuire.(1) New version has clarified the ultimate
motivation by adding sentences to the abstract and to the penultimate
paragraph of the introduction. (2) By combining a number of references and
equations we have managed to reduce the length by 2 page
The Initial Value Problem For Maximally Non-Local Actions
We study the initial value problem for actions which contain non-trivial
functions of integrals of local functions of the dynamical variable. In
contrast to many other non-local actions, the classical solution set of these
systems is at most discretely enlarged, and may even be restricted, with
respect to that of a local theory. We show that the solutions are those of a
local theory whose (spacetime constant) parameters vary with the initial value
data according to algebraic equations. The various roots of these algebraic
equations can be plausibly interpreted in quantum mechanics as different
components of a multi-component wave function. It is also possible that the
consistency of these algebraic equations imposes constraints upon the initial
value data which appear miraculous from the context of a local theory.Comment: 8 pages, LaTeX 2 epsilo
A graviton propagator for inflation
We construct the scalar and graviton propagator in quasi de Sitter space up
to first order in the slow roll parameter . After
a rescaling, the propagators are similar to those in de Sitter space with an
correction to the effective mass. The limit
corresponds to the E(3) vacuum that breaks de Sitter symmetry, but does not
break spatial isotropy and homogeneity. The new propagators allow for a
self-consistent, dynamical study of quantum back-reaction effects during
inflation.Comment: 23 page
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