79,816 research outputs found
A new species of the basal araneomorph spider genus Ectatosticta (Araneae, Hypochilidae) from China
The hypochilid spider Ectatosticta davidi (Simon) is redescribed on the basis of adults from Mt. Taibaishan in Shaanxi Province, China; the specimens from Qinghai Province previously identified as E. davidi by most modern authors belong to a new species described as E. deltshevi. Keywords: Araneae, Araneomorphae, Hypochilidae, Ectatosticta, Chin
Higgsed Gauge-flation
We study a variant of Gauge-flation where the gauge symmetry is spontaneously
broken by a Higgs sector. We work in the Stueckelberg limit and demonstrate
that the dynamics remain (catastrophically) unstable for cases where the gauge
field masses satisfy , where , is the
gauge coupling, is the gauge field vacuum expectation value, and is
the Hubble rate. We compute the spectrum of density fluctuations and
gravitational waves, and show that the model can produce observationally viable
spectra. The background gauge field texture violates parity, resulting in a
chiral gravitational wave spectrum. This arises due to an exponential
enhancement of one polarization of the spin-2 fluctuation of the gauge field.
Higgsed Gauge-flation can produce observable gravitational waves at
inflationary energy scales well below the GUT scale.Comment: 52 pages, 14 figure
Asymptotic Validity of the Bayes-Inspired Indifference Zone Procedure: The Non-Normal Known Variance Case
We consider the indifference-zone (IZ) formulation of the ranking and
selection problem in which the goal is to choose an alternative with the
largest mean with guaranteed probability, as long as the difference between
this mean and the second largest exceeds a threshold. Conservatism leads
classical IZ procedures to take too many samples in problems with many
alternatives. The Bayes-inspired Indifference Zone (BIZ) procedure, proposed in
Frazier (2014), is less conservative than previous procedures, but its proof of
validity requires strong assumptions, specifically that samples are normal, and
variances are known with an integer multiple structure. In this paper, we show
asymptotic validity of a slight modification of the original BIZ procedure as
the difference between the best alternative and the second best goes to
zero,when the variances are known and finite, and samples are independent and
identically distributed, but not necessarily normal
On the Invalidity of Fourier Series Expansions of Fractional Order
The purpose of this short paper is to show the invalidity of a Fourier series
expansion of fractional order as derived by G. Jumarie in a series of papers.
In his work the exponential functions are replaced by the
Mittag-Leffler functions over
the interval where and
is the period of the function i.e.,
$E_\alpha \left( ix^\alpha\right)=E_\alpha \left( i(x+M_\alpha)^\alpha\right).
A Comprehensive Coordinate Space Renormalization of Quantum Electrodynamics to 2-Loop Order
We develop a coordinate space renormalization of massless Quantum
Electrodynamics using the powerful method of differential renormalization. Bare
one-loop amplitudes are finite at non-coincident external points, but do not
accept a Fourier transform into momentum space. The method provides a
systematic procedure to obtain one-loop renormalized amplitudes with finite
Fourier transforms in strictly four dimensions without the appearance of
integrals or the use of a regulator. Higher loops are solved similarly by
renormalizing from the inner singularities outwards to the global one. We
compute all 1- and 2-loop 1PI diagrams, run renormalization group equations on
them and check Ward identities. The method furthermore allows us to discern a
particular pattern of renormalization under which certain amplitudes are seen
not to contain higher-loop leading logarithms. We finally present the
computation of the chiral triangle showing that differential renormalization
emerges as a natural scheme to tackle problems.Comment: 28 pages (figures not included
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