15,042 research outputs found
The Arbitrary Trajectory Quantization Method
The arbitrary trajectory quantization method (ATQM) is a time dependent
approach to quasiclassical quantization based on the approximate dual
relationship that exists between the quantum energy spectra and classical
periodic orbits. It has recently been shown however, that, for polygonal
billiards, the periodicity criterion must be relaxed to include closed
almost-periodic (CAP) orbit families in this relationship. In light of this
result, we reinvestigate the ATQM and show that at finite energies, a
smoothened quasiclassical kernel corresponds to the modified formula that
includes CAP families while the delta function kernel corresponding to the
periodic orbit formula is recovered at high energies. Several clarifications
are also provided.Comment: revtex, ps figure
The CWKB Method of Particle Production in Periodic Potential
In this work we study the particle production in time dependent periodic
potential using the method of complex time WKB (CWKB) approximation. In the
inflationary cosmology at the end of inflationary stage, the potential becomes
time dependent as well as periodic. Reheating occurs due to particle production
by the oscillating inflaton field. Using CWKB we obtain almost identical
results on catastrophic particle production as obtained by others.Comment: 17 pages, latex, 2 figure
Schroedinger Wheeler-DeWitt Equation In Multidimensional Cosmology
We study multidimensional cosmology to obtain the wavefunction of the
universe using wormhole dominance proposal. Using a prescription for time we
obtain the Schroedinger-Wheeler-DeWitt equation without any reference to WD
equation and WKB ansatz for WD wavefunction. It is found that the
Hartle-Hawking or wormhole-dominated boundary conditions serve as a seed for
inflation as well as for Gaussian type ansatz to Schroedinger-Wheeler-DeWitt
equation.Comment: 10 Pages, LaTeX, no figur
Semiclassical Inequivalence of Polygonalized Billiards
Polygonalization of any smooth billiard boundary can be carried out in
several ways. We show here that the semiclassical description depends on the
polygonalization process and the results can be inequivalent. We also establish
that generalized tangent-polygons are closest to the corresponding smooth
billiard and for de Broglie wavelengths larger than the average length of the
edges, the two are semiclassically equivalent.Comment: revtex, 4 ps figure
Periodic Orbits in Polygonal Billiards
We review some properties of periodic orbit families in polygonal billiards
and discuss in particular a sum rule that they obey. In addition, we provide
algorithms to determine periodic orbit families and present numerical results
that shed new light on the proliferation law and its variation with the genus
of the invariant surface. Finally, we deal with correlations in the length
spectrum and find that long orbits display Poisson fluctuations.Comment: 30 pages (Latex) including 11 figure
Economics and Efficiency of Organic Farming vis-Ă -vis Conventional Farming in India
Organic farming systems have attracted increasing attention over the last one decade because they are perceived to offer some solutions to the problems currently besetting the agricultural sector. Organic farming has the potential to provide benefits in terms of environmental protection, conservation of non-renewable resources and improved food quality. India is bestowed with lot of potential to produce all varieties of organic products due to its diverse agro-climatic regions. In several parts of the country, the inherited tradition of organic farming is an added advantage. This holds promise for the organic producers to tap the market which is growing steadily in the domestic market related to the export market. In India, the land under certification is around 2.8 million ha. But, there is considerable latent interest among farmers in conversion to organic farming. However, some farmers are reluctant to convert because of the perceived high costs and risks involved in organic farming. Despite the attention which has been paid to organic farming over the last few years, very little accessible information actually exists on the costs and returns of organic farming in India. The empirical evidences of efficiency analysis of organic and conventional farming systems are scarce or even absent. So, the present paper focuses mainly on the issues like economics and efficiency of organic farming vis-ďż˝-vis conventional farming in India. Four states namely Gujarat, Maharashtra, Punjab and U.P were purposively selected for the present study. Similarly, four major crops i.e., cotton, sugarcane, paddy and wheat were chosen for comparison. A model based non-parametric Data Envelopment Analysis (DEA) was used for analyzing the efficiency of the farming systems. The crop economics results showed a mixed response. Overall, it is concluded that the unit cost of production is lower in organic farming in case of cotton and sugarcane crops where as the same is lower in conventional farming for paddy and wheat crops. The DEA efficiency analysis conducted on different crops indicated that the efficiency levels are lower in organic farming when compared to conventional farming, relative to their production frontiers. The results conclude that there is ample scope for increasing the efficiency under organic farms.
- …