3,983 research outputs found
Fermions at unitarity and Haldane Exclusion Statistics
We consider a gas of neutral fermionic atoms at ultra-low temperatures, with
the attractive interaction tuned to Feshbach resonance. We calculate, the
variation of the chemical potential and the energy per particle as a function
of temperature by assuming the system to be an ideal gas obeying the Haldane-Wu
fractional exclusion statistics. Our results for the untrapped gas compare
favourably with the recently published Monte Carlo calculations of two groups.
For a harmonically trapped gas, the results agree with experiment, and also
with other published work.Comment: 4 pages, 1 postscript figur
Electronic Theses and Dissertations and Academia: A Preliminary Study From India
This paper outlines the current state
of doctoral theses collections in India, their usage, problems
with access, and the academic and research community’s
attitude towards digital archiving and electronic publishing in
Indian universities
Electronic Theses and Dissertations and Academia: A Preliminary Study From India
This paper outlines the current state
of doctoral theses collections in India, their usage, problems
with access, and the academic and research community’s
attitude towards digital archiving and electronic publishing in
Indian universities
D-branes in Unoriented Non-critical Strings and Duality in SO(N) and Sp(N) Gauge Theories
We exhibit exact conformal field theory descriptions of SO(N) and Sp(N) pairs
of Seiberg-dual gauge theories within string theory. The N=1 gauge theories
with flavour are realized as low energy limits of the worldvolume theories on
D-branes in unoriented non-critical superstring backgrounds. These unoriented
backgrounds are obtained by constructing exact crosscap states in the
SL(2,R)/U(1) coset conformal field theory using the modular bootstrap method.
Seiberg duality is understood by studying the behaviour of the boundary and
crosscap states under monodromy in the closed string parameter space.Comment: 23 pages, 2 figure
Critical Crossover Between Yosida-Kondo Dominant Regime and Magnetic Frustration Dominant Regime in the System of a Magnetic Trimer on a Metal Surface
Quantum Monte Carlo simulations were carried out for the system of a magnetic
trimer on a metal surface. The magnetic trimer is arranged in two geometric
configurations, viz., isosceles and equilateral triangles. The calculated
spectral density and magnetic susceptibility show the existence of two phases:
Yosida-Kondo dominant phase and magnetic frustration dominant phase.
Furthermore, a critical transition between these two phases can be induced by
changing the configuration of the magnetic trimers from isosceles to
equilateral triangle.Comment: 8 pages, 4 figures; accepted for publication in J. Phys. Soc. Jp
Exactly solvable toy models of unconventional magnetic alloys: Bethe Ansatz versus Renormalization Group method
We propose toy models of unconventional magnetic alloys, in which the density
of band states, , and hybridization, , are energy
dependent; it is assumed, however, that
, and hence an effective
electron-impurity coupling is
energy independent. In the renormalization group approach, the physics of the
system is assumed to be governed by only rather than by
separate forms of and . However, an exact Bethe
Ansatz solution of the toy Anderson model demonstrates a crucial role of a form
of inverse band dispersion .Comment: A final version. A previous one has been sent to Archive because of
my technical mistake. Sorr
Theory of the Half-Polarized Quantum Hall States
We report a theoretical analysis of the half-polarized quantum Hall states
observed in a recent experiment. Our numerical results indicate that the ground
state energy of the quantum Hall and states versus spin
polarization has a downward cusp at half the maximal spin polarization. We map
the two-component fermion system onto a system of excitons and describe the
ground state as a liquid state of excitons with non-zero values of exciton
angular momentum.Comment: 4 pages (RevTeX), 3 figures (PostScript), added reference
Topological Cigar and the c=1 String : Open and Closed
We clarify some aspects of the map between the c=1 string theory at self-dual
radius and the topologically twisted cigar at level one. We map the ZZ and FZZT
D-branes in the c=1 string theory at self dual radius to the localized and
extended branes in the topological theory on the cigar. We show that the open
string spectrum on the branes in the two theories are in correspondence with
each other, and their two point correlators are equal. We also find a
representation of an extended N=2 algebra on the worldsheet which incorporates
higher spin currents in terms of asymptotic variables on the cigar.Comment: 37 pages, 2 figures, corrections to section 3.1, references adde
Economic Analysis of Post-Harvest Loss and Marketing Efficiency in Guava (cv. Allahabad safeda) in Karnataka
Post-harvest losses (PHL) in guava (cv. Allahabad safeda) were estimated at the field and retail levels in Karnataka, and impact of this loss on marketing efficiency was studied. Results indicated that the total PHL was 13.29% consisting of field-level loss (9.17%) and retail level loss (4.12%). The producer's share was 51.52% and PHL, when included as an item of cost, reduced the share to 45.80%. PHL also reduced marketing efficiency index from 1.06 to 0.88, thereby indicating the importance of PHL and scope for minimizing it to improve the efficiency of the marketing system in guava
Classical Many-particle Clusters in Two Dimensions
We report on a study of a classical, finite system of confined particles in
two dimensions with a two-body repulsive interaction. We first develop a simple
analytical method to obtain equilibrium configurations and energies for few
particles. When the confinement is harmonic, we prove that the first transition
from a single shell occurs when the number of particles changes from five to
six. The shell structure in the case of an arbitrary number of particles is
shown to be independent of the strength of the interaction but dependent only
on its functional form. It is also independent of the magnetic field strength
when included. We further study the effect of the functional form of the
confinement potential on the shell structure. Finally we report some
interesting results when a three-body interaction is included, albeit in a
particular model.Comment: Minor corrections, a few references added. To appear in J. Phys:
Condensed Matte
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