5,162 research outputs found
Moving frames for cotangent bundles
Cartan's moving frames method is a standard tool in riemannian geometry. We
set up the machinery for applying moving frames to cotangent bundles and its
sub-bundles defined by non-holonomic constraints.Comment: 13 pages, to appear in Rep. Math. Phy
Quantum phase transitions and decoupling of magnetic sublattices in the quasi-two-dimensional Ising magnet Co3V2O8 in a transverse magnetic field
The application of a magnetic field transverse to the easy axis, Ising
direction in the quasi-two-dimensional Kagome staircase magnet, Co3V2O8,
induces three quantum phase transitions at low temperatures, ultimately
producing a novel high field polarized state, with two distinct sublattices.
New time-of-flight neutron scattering techniques, accompanied by large angular
access, high magnetic field infrastructure allow the mapping of a sequence of
ferromagnetic and incommensurate phases and their accompanying spin
excitations. At least one of the transitions to incommensurate phases at \mu
0Hc1~6.25 T and \mu 0Hc2~7 T is discontinuous, while the final quantum critical
point at \mu 0Hc3~13 T is continuous.Comment: 5 pages manuscript, 3 pages supplemental materia
Analytical modelling of positional and thematic uncertainties in the integration of remote sensing and geographical information systems
This paper describes three aspects of uncertainty in geographical information systems (GIS) and remote sensing. First, the positional uncertainty of an area object in a GIS is discussed as a function of positional uncertainties of line segments and boundary line features. Second, the thematic uncertainty of a classified remote sensing image is described using the probability vectors from a maximum likelihood classification. Third, the 'S-band' model is used to quantify uncertainties after combining GIS and remote sensing data.Department of Land Surveying and Geo-Informatic
Maximally extended, explicit and regular coverings of the Schwarzschild - de Sitter vacua in arbitrary dimension
Maximally extended, explicit and regular coverings of the Schwarzschild - de
Sitter family of vacua are given, first in spacetime (generalizing a result due
to Israel) and then for all dimensions (assuming a sphere). It is
shown that these coordinates offer important advantages over the well known
Kruskal - Szekeres procedure.Comment: 12 pages revtex4 5 figures in color. Higher resolution version at
http://www.astro.queensu.ca/~lake/regularcoordinates.pd
Synthesis, Structures, and Electronic Properties of O- and S-Heterocyclic Carbene Complexes of Iridium, Copper, Silver, and Gold
Pressure as a Source of Gravity
The active mass density in Einstein's theory of gravitation in the analog of
Poisson's equation in a local inertial system is proportional to .
Here is the density of energy and its pressure for a perfect fluid.
By using exact solutions of Einstein's field equations in the static case we
study whether the pressure term contributes towards the mass
Lagrangian description of the fluid flow with vorticity in the relativistic cosmology
We develop the Lagrangian perturbation theory in the general relativistic
cosmology, which enables us to take into account the vortical effect of the
dust matter. Under the Lagrangian representation of the fluid flow, the
propagation equation for the vorticity as well as the density is exactly
solved. Based on this, the coupling between the density and vorticity is
clarified in a non-perturbative way. The relativistic correspondence to the
Lagrangian perturbation theory in the Newtonian cosmology is also emphasized.Comment: 14 pages (RevTeX); accepted for publication in Phys. Rev.
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