The Bianchi IX model in Loop Quantum Cosmology

The Bianchi IX model has been used often to investigate the structure close to singularities of general relativity. Its classical chaos is expected to have, via the BKL scenario, implications even for the approach to general inhomogeneous singularities. Thus, it is a popular model to test consequences of modifications to general relativity suggested by quantum theories of gravity. This paper presents a detailed proof that modifications coming from loop quantum gravity lead to a non-chaotic effective behavior. The way this is realized, independently of quantization ambiguities, suggests a new look at initial and final singularities

Bis[4-amino-N-(pyrimidin-2-yl)benzene­sulfonamidato]-κ2 N,N′;κN-aqua­bis­(dimethyl­formamide-κO)cadmium(II) monohydrate

In the title compound, [Cd(C10H9N4O2S)2(C3H7NO)2(H2O)]·H2O, the CdII ion displays a grossly distorted octa­hedral (or irregular) mer-CdN3O3 coodination polyhdron arising from its coordination by one N,N′-bidentate sulfadiazinate anion, one monodentate sulfadiazinate anion, two O-bonded dimethyl­formamide molecules and one water mol­ecule. A short Cd⋯N contact [2.890 (3) Å] to the monodentate sulfadiazinate ion also occurs. The dihedral angles between the planes of the aromatic rings of the anions are 86.81 (14) and 68.65 (14)°. The crystal structure features inter­molecular N—H⋯O, O—H⋯O and O—H⋯N hydrogen bonds

Magnetic Transition in the Kondo Lattice System CeRhSn2

Our resistivity, magnetoresistance, magnetization and specific heat data provide unambiguous evidence that CeRhSn2 is a Kondo lattice system which undergoes magnetic transition below 4 K.Comment: 3 pages text and 5 figure

Moral hazard and the division of labor in agricultural land leases

land lease contracts, moral hazard, contract duration, division of labor, Land Economics/Use,

MANAGEMENT PRACTICES AND LEASE ARRANGEMENTS USED BY OKLAHOMA WHEAT, WHEAT PASTURE, AND WHEAT PASTURE LIVESTOCK PRODUCERS

Winter wheat is grown for three purposes in the Southern Plains, grain-only, forage-only, and as a dual-purpose forage plus grain crop. The USDA's wheat cropping practices survey does not differentiate among the three uses. Little information on actual production practices across use is available. Results of a survey are presented.Crop Production/Industries,

cis-Bis[4-amino-N-(pyrimidin-2-yl)benzene­sulfonamido-κ2 N,N′]bis­(dimethyl sulfoxide-κO)cadmium

The complete mol­ecule of the title compound, [Cd(C10H9N4O2S)2(C2H6OS)2], is completed by the application of a twofold rotation axis. The CdII atom is six coordinated by two bidentate sulfadiazinate anions and two dimethyl­sulfoxide mol­ecules. The resulting N4O2 donor set displays a distorted trigonal–prismatic coordination geometry. The S atom and methyl groups of dimethyl­sulfoxide are disordered over two sets of sites, with site occupancies of 0.715 (4) and 0.285 (4). The crystal structure features inter­molecular N—H⋯N and N—H⋯O hydrogen bonds that lead to the formation of layers in the ab plane

Background independent quantization and wave propagation

We apply a type of background independent "polymer" quantization to a free scalar field in a flat spacetime. Using semi-classical states, we find an effective wave equation that is both nonlinear and Lorentz invariance violating. We solve this equation perturbatively for several cases of physical interest, and show that polymer corrections to solutions of the Klein-Gordon equation depend on the amplitude of the field. This leads to an effective dispersion relation that depends on the amplitude, frequency and shape of the wave-packet, and is hence distinct from other modified dispersion relations found in the literature. We also demonstrate that polymer effects tend to accumulate with time for plane-symmetric waveforms. We conclude by discussing the possibility of measuring deviations from the Klein-Gordon equation in particle accelerators or astrophysical observations.Comment: 15 pages, minor revision to match PRD versio

Monotone Grid Drawings of Planar Graphs

A monotone drawing of a planar graph $G$ is a planar straight-line drawing of $G$ where a monotone path exists between every pair of vertices of $G$ in some direction. Recently monotone drawings of planar graphs have been proposed as a new standard for visualizing graphs. A monotone drawing of a planar graph is a monotone grid drawing if every vertex in the drawing is drawn on a grid point. In this paper we study monotone grid drawings of planar graphs in a variable embedding setting. We show that every connected planar graph of $n$ vertices has a monotone grid drawing on a grid of size $O(n)\times O(n^2)$, and such a drawing can be found in O(n) time

Rapid generation of angular momentum in bounded magnetized plasma

Direct numerical simulations of two-dimensional decaying MHD turbulence in bounded domains show the rapid generation of angular momentum in nonaxisymmetric geometries. It is found that magnetic fluctuations enhance this mechanism. On a larger time scale, the generation of a magnetic angular momentum, or angular field, is observed. For axisymmetric geometries, the generation of angular momentum is absent; nevertheless, a weak magnetic field can be observed. The derived evolution equations for both the angular momentum and angular field yield possible explanations for the observed behavior