16,493 research outputs found
Symplectic Reduction and Symmetry Algebra in Boundary Chern-Simons theory
We derive the Kac-Moody algebra and Virasoro algebra in Chern-Simons theory
with boundary by using the symplectic reduction method and the Noether
procedures.Comment: References are adde
GPU accelerated real-time multi-functional spectral-domain optical coherence tomography system at 1300 nm.
We present a GPU accelerated multi-functional spectral domain optical coherence tomography system at 1300 nm. The system is capable of real-time processing and display of every intensity image, comprised of 512 pixels by 2048 A-lines acquired at 20 frames per second. The update rate for all four images with size of 512 pixels by 2048 A-lines simultaneously (intensity, phase retardation, flow and en face view) is approximately 10 frames per second. Additionally, we report for the first time the characterization of phase retardation and diattenuation by a sample comprised of a stacked set of polarizing film and wave plate. The calculated optic axis orientation, phase retardation and diattenuation match well with expected values. The speed of each facet of the multi-functional OCT CPU-GPU hybrid acquisition system, intensity, phase retardation, and flow, were separately demonstrated by imaging a horseshoe crab lateral compound eye, a non-uniformly heated chicken muscle, and a microfluidic device. A mouse brain with thin skull preparation was imaged in vivo and demonstrated the capability of the system for live multi-functional OCT visualization
Comments on "Entropy of 2D Black Holes from Counting Microstates"
In a recent letter, Cadoni and Mignemi proposed a formulation for the
statistical computation of the 2D black holes entropy. We present a criticism
about their formulation.Comment: 5 pages, Latex, no figure
Hidden Local Symmetry and Infinite Tower of Vector Mesons for Baryons
In an effort to access dense baryonic matter relevant for compact stars in a
unified framework that handles both single baryon and multibaryon systems on
the same footing, we first address a holographic dual action for a single
baryon focusing on the role of the infinite tower of vector mesons
deconstructed from five dimensions. To leading order in 't Hooft coupling
, one has the Bogomol'nyi-Prasad-Sommerfield (BPS)
Skyrmion that results when the warping of the bulk background and the
Chern-Simons term in the Sakai-Sugimoto D4/D8- model are
ignored. The infinite tower was found by Sutcliffe to induce flow to a
conformal theory, i.e., the BPS. We compare this structure to that of the SS
model consisting of a 5D Yang-Mills action in warped space and the Chern-Simons
term in which higher vector mesons are integrated out while preserving hidden
local symmetry and valid to and in the chiral counting.
We point out the surprisingly important role of the meson that figures
in the Chern-Simons term that encodes chiral anomaly in the baryon structure
and that may be closely tied to short-range repulsion in nuclear interactions.Comment: 9 pages, REVTeX, to be published in Phys. Rev.
The fate of North Atlantic Subtropical Mode Water in the FLAME model
Author Posting. © American Meteorological Society, 2014. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 44 (2014): 1354–1371, doi:10.1175/JPO-D-13-0202.1.North Atlantic Subtropical Mode Water, also known as Eighteen Degree Water (EDW), has the potential to store heat anomalies through its seasonal cycle: the water mass is in contact with the atmosphere in winter, isolated from the surface for the rest of the year, and reexposed the following winter. Though there has been recent progress in understanding EDW formation processes, an understanding of the fate of EDW following formation remains nascent. Here, particles are launched within the EDW of an eddy-resolving model, and their fate is tracked as they move away from the formation region. Particles in EDW have an average residence time of ~10 months, they follow the large-scale circulation around the subtropical gyre, and stratification is the dominant criteria governing the exit of particles from EDW. After sinking into the layers beneath EDW, particles are eventually exported to the subpolar gyre. The spreading of particles is consistent with the large-scale potential vorticity field, and there are signs of a possible eddy-driven mean flow in the southern portion of the EDW domain. The authors also show that property anomalies along particle trajectories have an average integral time scale of ~3 months for particles that are in EDW and ~2 months for particles out of EDW. Finally, it is shown that the EDW turnover time for the model in an Eulerian frame (~3 yr) is consistent with the turnover time computed from the Lagrangian particles provided that the effects of exchange between EDW and the surrounding waters are included.The authors are thankful for financial
support from the U.S. National Science Foundation
for S. F. G., M. S. L., Y.-O. K., and J. J. P.2014-11-0
- …