27,981 research outputs found
Function with its Fourier transform supported on annulus and eigenfunction of Laplacian
We explore the possibilities of reaching the characterization of
eigenfunction of Laplacian as a degenerate case of the inverse Paley-Wiener
theorem (characterizing functions whose Fourier transform is supported on a
compact annulus) for the Riemannian symmetric spaces of noncompact type. Most
distinguished prototypes of these spaces are the hyperbolic spaces. The
statement and the proof of the main result work mutatis-mutandis for a number
of spaces including Euclidean spaces and Damek-Ricci spaces.Comment: 24 page
Effect of meditation on scaling behavior and complexity of human heart rate variability
The heart beat data recorded from samples before and during meditation are
analyzed using two different scaling analysis methods. These analyses revealed
that mediation severely affects the long range correlation of heart beat of a
normal heart. Moreover, it is found that meditation induces periodic behavior
in the heart beat. The complexity of the heart rate variability is quantified
using multiscale entropy analysis and recurrence analysis. The complexity of
the heart beat during mediation is found to be more.Comment: 7 Figure
Neutrino Radar
We point out that with improving our present knowledge of experimental
neutrino physics it will be possible to locate nuclear powered vehicles like
submarines, aircraft carriers and UFOs and detect nuclear testing. Since
neutrinos cannot be shielded, it will not be possible to escape these
detection. In these detectors it will also be possible to perform neutrino
oscillation experiments during any nuclear testing.Comment: 8 pages late
Effect of heavy ion irradiation on microstructure and electron density distribution of zirconium alloy characterised by X-ray diffraction technique
Different techniques of the X-ray Diffraction Line Profile Analysis (XRDLPA)
have been used to assess the microstructure of the irradiated
Zr-1.0%Nb-1.0%Sn-0.1%Fe alloy. The domain size, microstrain, density of
dislocation and the stacking fault probabilities of the irradiated alloy have
been estimated as a function of dose by the Williamson-Hall Technique, Modified
Rietveld Analysis and the Double Voigt Method. A clear signature in the
increase in the density of dislocation with the dose of irradiated was
revealed. The analysis also estimated the average density of dislocation in the
major slip planes after irradiation. For the first time, we have established
the changes in the electron density distribution due to irradiation by X-ray
diffraction technique. We could estimate the average displacement of the atoms
and the lattice strain caused due to irradiation from the changes in the
electron density distribution as observed in the contour plots
Pure and Hybrid Evolutionary Computing in Global Optimization of Chemical Structures: from Atoms and Molecules to Clusters and Crystals
The growth of evolutionary computing (EC) methods in the exploration of
complex potential energy landscapes of atomic and molecular clusters, as well
as crystals over the last decade or so is reviewed. The trend of growth
indicates that pure as well as hybrid evolutionary computing techniques in
conjunction of DFT has been emerging as a powerful tool, although work on
molecular clusters has been rather limited so far. Some attempts to solve the
atomic/molecular Schrodinger Equation (SE) directly by genetic algorithms (GA)
are available in literature. At the Born-Oppenheimer level of approximation
GA-density methods appear to be a viable tool which could be more extensively
explored in the coming years, specially in the context of designing molecules
and materials with targeted properties
On the Schwartz space isomorphism theorem for rank one symmetric space
In this paper we give a simpler proof of the -Schwartz space isomorphism
under the Fourier transform for the class of functions of left
-type on a Riemannian symmetric space of rank one. Our treatment rests
on Anker's \cite{A} proof of the corresponding result in the case of left
-invariant functions on . Thus we give a proof which relies only on the
Paley--Wiener theorem.Comment: 16 page
Beurling's Theorem and characterization of heat kernel for Riemannian Symmetric spaces of noncompact type
We prove Beurling's theorem for rank 1 Riemmanian symmetric spaces and relate
it to the characterization of the heat kernel of the symmetric space
Asymptotic mean value property for eigenfunctions of the Laplace-Beltrami operator on Damek-Ricci spaces
Let be a Damek-Ricci space equipped with the Laplace-Beltrami operator
. In this paper we characterize all eigenfunctions of through
sphere, ball and shell averages as the radius (of sphere, ball or shell) tends
to infinity
Beurling's Theorem and Morgan's Theorem for Step Two Nilpotent Lie Groups
We prove Beurling's theorem and Morgan's theorem for step two
nilpotent Lie groupsComment: 20 page
Beurling's Theorem for
We prove Beurling's theorem for the full group . This is the {\em
master theorem} in the quantitative uncertainty principle as all the other
theorems of this genre follow from it
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