298,536 research outputs found
High Pt hadron-hadron correlations
We propose the formulation of a dihadron fragmentation function in terms of
parton matrix elements. Under the collinear factorization approximation and
facilitated by the cut-vertex technique, the two hadron inclusive cross section
at leading order (LO) in e+ e- annihilation is shown to factorize into a short
distance parton cross section and the long distance dihadron fragmentation
function. We also derive the DGLAP evolution equation of this function at
leading log. The evolution equation for the non-singlet and singlet quark
fragmentation function and the gluon fragmentation function are solved
numerically with the initial condition taken from event generators.
Modifications to the dihadron fragmentation function from higher twist
corrections in DIS off nuclei are computed. Results are presented for cases of
physical interest.Comment: 7 pages, 8 figures, Latex, Proceedings of Hot Quarks 2004, July
18-24, Taos, New Mexic
Azimuthal asymmetry in transverse energy flow in nuclear collisions at high energies
The azimuthal pattern of transverse energy flow in nuclear collisions at RHIC
and LHC energies is considered. We show that the probability distribution of
the event-by-event azimuthal disbalance in transverse energy flow is
essentially sensitive to the presence of the semihard minijet component.Comment: 6 pages, 2 figure
Gravitational Collapse of Circularly Symmetric Stiff Fluid with Self-Similarity in 2+1 Gravity
Linear perturbations of homothetic self-similar stiff fluid solutions,
, with circular symmetry in 2+1 gravity are studied. It is found that,
except for those with and , none of them is stable and all have
more than one unstable mode. Hence, {\em none of these solutions can be
critical}.Comment: latex file, 1 figure; last version to appear in Prog. Theor. Phy
Input Fast-Forwarding for Better Deep Learning
This paper introduces a new architectural framework, known as input
fast-forwarding, that can enhance the performance of deep networks. The main
idea is to incorporate a parallel path that sends representations of input
values forward to deeper network layers. This scheme is substantially different
from "deep supervision" in which the loss layer is re-introduced to earlier
layers. The parallel path provided by fast-forwarding enhances the training
process in two ways. First, it enables the individual layers to combine
higher-level information (from the standard processing path) with lower-level
information (from the fast-forward path). Second, this new architecture reduces
the problem of vanishing gradients substantially because the fast-forwarding
path provides a shorter route for gradient backpropagation. In order to
evaluate the utility of the proposed technique, a Fast-Forward Network (FFNet),
with 20 convolutional layers along with parallel fast-forward paths, has been
created and tested. The paper presents empirical results that demonstrate
improved learning capacity of FFNet due to fast-forwarding, as compared to
GoogLeNet (with deep supervision) and CaffeNet, which are 4x and 18x larger in
size, respectively. All of the source code and deep learning models described
in this paper will be made available to the entire research communityComment: Accepted in the 14th International Conference on Image Analysis and
Recognition (ICIAR) 2017, Montreal, Canad
Lower dimensional volumes and the Kastler-Kalau-Walze type theorem for Manifolds with Boundary
In this paper, we define lower dimensional volumes of spin manifolds with
boundary. We compute the lower dimensional volume for
5-dimensional and 6-dimensional spin manifolds with boundary and we also get
the Kastler-Kalau-Walze type theorem in this case
Model-Independent Measurement of the Primordial Power Spectrum
In inflationary models with minimal amount of gravity waves, the primordial
power spectrum of density fluctuations, , together with the basic
cosmological parameters, completely specify the predictions for the cosmic
microwave background (CMB) anisotropy and large scale structure. Here we show
how we can strongly constrain both and the cosmological parameters
by combining the data from the Microwave Anisotropy Probe (MAP) and the galaxy
redshift survey from the Sloan Digital Sky Survey (SDSS). We allow
to be a free function, and thus probe features in the primordial power spectrum
on all scales. MAP and SDSS have scale-dependent measurement errors that
decrease in opposite directions on astrophysically interesting scales; they
complement each other and allow the measurement of the primordial power
spectrum independent of inflationary models, giving us valuable information on
physics in the early Universe, and providing clues to the correct inflationary
model.Comment: 4 pages including 4 figures. To appear in "Particle Physics and the
Early Universe (COSMO-98)", editor David O. Caldwell (American Institute of
Physics
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