12,981 research outputs found
Coherent state triplets and their inner products
It is shown that if H is a Hilbert space for a representation of a group G,
then there are triplets of spaces F_H, H, F^H, in which F^H is a space of
coherent state or vector coherent state wave functions and F_H is its dual
relative to a conveniently defined measure. It is shown also that there is a
sequence of maps F_H -> H -> F^H which facilitates the construction of the
corresponding inner products. After completion if necessary, the F_H, H, and
F^H, become isomorphic Hilbert spaces. It is shown that the inner product for H
is often easier to evaluate in F_H than F^H. Thus, we obtain integral
expressions for the inner products of coherent state and vector coherent state
representations. These expressions are equivalent to the algebraic expressions
of K-matrix theory, but they are frequently more efficient to apply. The
construction is illustrated by many examples.Comment: 33 pages, RevTex (Latex2.09) This paper is withdrawn because it
contained errors that are being correcte
An exactly solvable model of a superconducting to rotational phase transition
We consider a many-fermion model which exhibits a transition from a
superconducting to a rotational phase with variation of a parameter in its
Hamiltonian. The model has analytical solutions in its two limits due to the
presence of dynamical symmetries. However, the symmetries are basically
incompatible with one another; no simple solution exists in intermediate
situations. Exact (numerical) solutions are possible and enable one to study
the behavior of competing but incompatible symmetries and the phase transitions
that result in a semirealistic situation. The results are remarkably simple and
shed light on the nature of phase transitions.Comment: 11 pages including 1 figur
Investigation of nonlinear interaction phenomena in the ionosphere
Ionospheric phenomena as thermal radiation noise, propagation of naturally occurring radio noise through ionosphere, and generation of very low frequency emission
Evaluation of an On-Campus Program Bridging the Theory-Practice Gap in Occupational Therapy Education: Student Perspective
The transfer of learning from an academic setting to fieldwork and vice versa is not straightforward and
occupational therapy students often report this as challenging. In acknowledgement of this, the fieldwork
placement learning structure within the Bachelor and Master occupational therapy entry-level programs at
a higher education institute was redesigned to enhance links between taught content at university and
fieldwork placement. The aim of this study was to explore occupational therapy students’ perspectives of
this new educational initiative. The students attended university for a set number of days over the course
of their first and second fieldwork placements. The sessions were focused on assisting students to make
connections between theory taught at university to the practice setting and allow time for reflection and
consolidation of learning. One hundred and fifteen occupational therapy students completed an
anonymized online questionnaire to evaluate their experiences consisting of open and closed questions.
Qualitative data was analyzed using thematic analysis and Likert Scale data was analyzed descriptively.
Three key themes were identified from the qualitative information: reflection, support, and understanding
and knowledge. The students reported the sessions provided time for reflection, which enabled them to
link theory to practice more clearly and peer support was highly regarded. The introduction of university
days during fieldwork education was overall positively received by students. This educational approach
helped students to better understand theory and promoted reflection on practice experiences. This may
be a useful approach to bridge the gap between theory and practice
History And Development Of The Jasper Negro High School 1975 to 1935 at Jasper, Texas
Since we began our work here In 1924, we have been asked many times by persons In various parts of the state end out of the state Just how we have done what we have in a community lite this, which is almost wholly rural, where the colored people own such little and apparently are illiterate and so indifferent to educational progress. Supervisors from the Department of Education in Texas and from Prairie View State College have visited us from time to time and have inquired How did you do it? Field agents from the General Education Board and the Plater Board have come to us several times and they always expressed themselves as agreeably surprised at our accomplishments and asked us to explain how we did it* Even our lovable local people who have been in the thickest of the fight, so to speak, and members of too teaching staff and members of the local Board of Education have asked how we did it. It Is the purpose of this study to make an effort, though a feeble one, to explain briefly how we did it The method used in this study has been to Interview old residents, both white and colored, and to make personal observations
On giant piezoresistance effects in silicon nanowires and microwires
The giant piezoresistance (PZR) previously reported in silicon nanowires is
experimentally investigated in a large number of surface depleted silicon nano-
and micro-structures. The resistance is shown to vary strongly with time due to
electron and hole trapping at the sample surfaces. Importantly, this time
varying resistance manifests itself as an apparent giant PZR identical to that
reported elsewhere. By modulating the applied stress in time, the true PZR of
the structures is found to be comparable with that of bulk silicon
Representations of the Weyl group and Wigner functions for SU(3)
Bases for SU(3) irreps are constructed on a space of three-particle tensor
products of two-dimensional harmonic oscillator wave functions. The Weyl group
is represented as the symmetric group of permutations of the particle
coordinates of these space. Wigner functions for SU(3) are expressed as
products of SU(2) Wigner functions and matrix elements of Weyl transformations.
The constructions make explicit use of dual reductive pairs which are shown to
be particularly relevant to problems in optics and quantum interferometry.Comment: : RevTex file, 11 pages with 2 figure
Vector coherent state representations, induced representations, and geometric quantization: II. Vector coherent state representations
It is shown here and in the preceeding paper (quant-ph/0201129) that vector
coherent state theory, the theory of induced representations, and geometric
quantization provide alternative but equivalent quantizations of an algebraic
model. The relationships are useful because some constructions are simpler and
more natural from one perspective than another. More importantly, each approach
suggests ways of generalizing its counterparts. In this paper, we focus on the
construction of quantum models for algebraic systems with intrinsic degrees of
freedom. Semi-classical partial quantizations, for which only the intrinsic
degrees of freedom are quantized, arise naturally out of this construction. The
quantization of the SU(3) and rigid rotor models are considered as examples.Comment: 31 pages, part 2 of two papers, published versio
Collective states of the odd-mass nuclei within the framework of the Interacting Vector Boson Model
A supersymmetric extension of the dynamical symmetry group of
the Interacting Vector Boson Model (IVBM), to the orthosymplectic group
is developed in order to incorporate fermion degrees of
freedom into the nuclear dynamics and to encompass the treatment of odd mass
nuclei. The bosonic sector of the supergroup is used to describe the complex
collective spectra of the neighboring even-even nuclei and is considered as a
core structure of the odd nucleus. The fermionic sector is represented by the
fermion spin group .
The so obtained, new exactly solvable limiting case is applied for the
description of the nuclear collective spectra of odd mass nuclei. The
theoretical predictions for different collective bands in three odd mass
nuclei, namely , and from rare earth region are
compared with the experiment. The transition probabilities for the
and between the states of the ground band are also
studied. The important role of the symplectic structure of the model for the
proper reproduction of the behavior is revealed. The obtained results
reveal the applicability of the models extension.Comment: 18 pages, 8 figure
Prelaunch testing of the GEOS-3 laser reflector array
The prelaunch testing performed on the Geos-3 laser reflector array before launch was used to determine the lidar cross section of the array and the distance of the center of gravity of the satellite from the center of gravity of reflected laser pulses as a function of incidence angle. Experimental data are compared to computed results
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