65
65

Sep 23, 2013
09/13

by
G. Hector; E. Macías-Virgós; E. Sanmartín-Carbón

texts

######
eye 65

######
favorite 0

######
comment 0

Let $(M,\mathcal{F})$ be a foliated manifold. We prove that there is a canonical isomorphism between the complex of base-like forms $\Omega^*_b(M,\mathcal{F})$ of the foliation and the "De Rham complex" of the space of leaves $M/\mathcal{F}$ when considered as a "diffeological" quotient. Consequently, the two corresponding cohomology groups $H^*_b(M,\mathcal{F})$ and $H^*(M/\mathcal{F})$ are isomorphic.

Source: http://arxiv.org/abs/0903.2871v1

33
33

Sep 23, 2013
09/13

by
Babak Vakili

texts

######
eye 33

######
favorite 0

######
comment 0

The effects of noncommutativity and deformed Heisenberg algebra on the evolution of a two dimensional minisuperspace quantum cosmological model are investigated.

Source: http://arxiv.org/abs/0903.2789v1

30
30

Sep 23, 2013
09/13

by
S. Qian; L. Zhu; S. Zola; W. Liao; L. Liu; L. Li; M. Winiarski; E. Kuligowska; J. Kreiner

texts

######
eye 30

######
favorite 0

######
comment 0

HS 0705+6700 is a short-period (P=2.3 hours), close binary containing a hot sdB-type primary and a fully convective secondary. We have monitored this eclipsing binary for more than 2 years and as a result, 32 times of light minimum were obtained. Based on our new eclipse times together with these compiled from the literature, it is discovered that the O-C curve of HS 0705+6700 shows a cyclic variation with a period of 7.15 years and a semiamplitude of 92.4 s. The periodic change was analyzed...

Source: http://arxiv.org/abs/0903.1357v2

45
45

Sep 23, 2013
09/13

by
Sarah E. Ragan; Edwin A. Bergin; Robert A. Gutermuth

texts

######
eye 45

######
favorite 0

######
comment 0

We have conducted a survey of a sample of infrared-dark clouds (IRDCs) with the Spitzer Space Telescope in order to explore their mass distribution. We present a method for tracing mass using dust absorption against the bright Galactic background at 8 microns. The IRDCs in this sample are comprised of tens of clumps, ranging in sizes from 0.02 to 0.3 pc in diameter and masses from 0.5 to a few 10 Msun, the broadest dynamic range in any clump mass spectrum study to date. Structure with this...

Source: http://arxiv.org/abs/0903.2771v1

38
38

Sep 23, 2013
09/13

by
F. Breitling

texts

######
eye 38

######
favorite 0

######
comment 0

This work reports on the discovery of HESS J1514-591, a VHE gamma-ray source found at the pulsar wind nebula (PWN) MSH 15-52 and its associated pulsar PSR B1509-58. The discovery was made with the High Energy Stereoscopic System (H.E.S.S.), which currently provides the most sensitive measurement in the energy range of about 0.2-100 TeV. This analysis is the first to include all H.E.S.S. data from observations dedicated to MSH 15-52. The corresponding flux above 1 TeV is...

Source: http://arxiv.org/abs/0903.2056v2

41
41

Jul 22, 2013
07/13

by
Jorge Noronha; Miklos Gyulassy; Giorgio Torrieri

texts

######
eye 41

######
favorite 0

######
comment 0

We show that far zone Mach and diffusion wake ``holograms'' produced by supersonic strings in anti--de Sitter space/conformal field theory (AdS/CFT) correspondence do not lead to observable conical angular correlations in the strict $N_c\to\infty$ supergravity limit if Cooper-Frye hadronization is assumed. However, a special {\em nonequilibrium} ``neck'' zone near the jet is shown to produce an apparent sonic boom azimuthal angle distribution that is roughly independent of the heavy quark's...

Source: http://arxiv.org/abs/0807.1038v2

26
26

Sep 23, 2013
09/13

by
Wen-Li Yang; Yao-Zhong Zhang; Samuel Kault

texts

######
eye 26

######
favorite 0

######
comment 0

Based on the particular orderings introduced for the positive roots of finite dimensional basic Lie superalgebras, we construct the explicit differential operator representations of the $osp(2r|2n)$ and $osp(2r+1|2n)$ superalgebras and the explicit free field realizations of the corresponding current superalgebras $osp(2r|2n)_k$ and $osp(2r+1|2n)_k$ at an arbitrary level $k$. The free field representations of the corresponding energy-momentum tensors and screening currents of the first kind are...

Source: http://arxiv.org/abs/0810.3719v2

33
33

Sep 23, 2013
09/13

by
Jong-Geon Bu; Jae Hyung Yee; Hyeong-Chan Kim

texts

######
eye 33

######
favorite 0

######
comment 0

The differential structure on the kappa-Minkowski spacetime from Jordanian twist of Weyl algebra is constructed, and it is shown to be closed in 4-dimensions in contrast to the conventional formulation. Based on this differential structure, we have formulated a scalar field theory in this kappa-Minkowski spacetime.

Source: http://arxiv.org/abs/0903.0040v2

43
43

Sep 23, 2013
09/13

by
Ghaya Baili; Mehdi Alouini; Thierry Malherbe; Daniel Dolfi; Isabelle Sagnes; Fabien Bretenaker

texts

######
eye 43

######
favorite 0

######
comment 0

The transition between the class-B and class-A dynamical behaviors of a semiconductor laser is directly observed by continuously controlling the lifetime of the photons in a cavity of sub-millimetric to centimetric length. It is experimentally and theoretically proved that the transition from a resonant to an overdamped behavior occurs progressively, without any discontinuity. In particular, the intermediate regime is found to exhibit features typical from both the class-A and class-B regimes....

Source: http://arxiv.org/abs/0903.2827v1

36
36

Sep 23, 2013
09/13

by
D. Speer; R. Eichhorn; P. Reimann

texts

######
eye 36

######
favorite 0

######
comment 0

We consider an overdamped Brownian particle, exposed to a two-dimensional, square lattice potential and a rectangular ac-drive. Depending on the driving amplitude, the linear response to a weak dc-force along a lattice symmetry axis consist in a mobility in basically any direction. In particular, motion exactly opposite to the applied dc-force may arise. Upon changing the angle of the dc-force relatively to the square lattice, the particle motion remains predominantly opposite to the dc-force....

Source: http://arxiv.org/abs/0903.2736v1

30
30

Sep 23, 2013
09/13

by
H. W. Diehl; H. Chamati

texts

######
eye 30

######
favorite 0

######
comment 0

The critical dynamics of relaxational stochastic models with nonconserved $n$-component order parameter $\bm{\phi}$ and no coupling to other slow variables ("model A") is investigated in film geometries for the cases of periodic and free boundary conditions. The Hamiltonian $\mathcal{H}$ governing the stationary equilibrium distribution is taken to be O(n) symmetric and to involve, in the case of free boundary conditions, the boundary terms $\int_{\mathfrak{B}_j}\mathring{c}_j...

Source: http://arxiv.org/abs/0810.5244v2

39
39

Sep 23, 2013
09/13

by
Marco Pavone; Stephen L. Smith; Francesco Bullo; Emilio Frazzoli

texts

######
eye 39

######
favorite 0

######
comment 0

In this paper we study a dynamic vehicle routing problem in which there are multiple vehicles and multiple classes of demands. Demands of each class arrive in the environment randomly over time and require a random amount of on-site service that is characteristic of the class. To service a demand, one of the vehicles must travel to the demand location and remain there for the required on-site service time. The quality of service provided to each class is given by the expected delay between the...

Source: http://arxiv.org/abs/0903.2695v1

22
22

Jul 20, 2013
07/13

by
L. Herrera; A. Di Prisco; E. Fuenmayor; O. Troconis

texts

######
eye 22

######
favorite 0

######
comment 0

The Misner and Sharp approach to the study of gravitational collapse is extended to the viscous dissipative case in, both, the streaming out and the diffusion approximations. The dynamical equation is then coupled to causal transport equations for the heat flux, the shear and the bulk viscosity, in the context of Israel--Stewart theory, without excluding the thermodynamics viscous/heat coupling coefficients. The result is compared with previous works where these later coefficients were...

Source: http://arxiv.org/abs/0804.3584v2