1,300 research outputs found
At home in the academic library? A study of student feelings of “homeness”
A recent focus in academic library design is as a third place: a home from home. Research has yet to interrogate what it means to be “at home,, and if academic libraries are treated like, and feel like home to students. Seamon’s model provides a framework for understanding the qualities associated with homeness, across the five dimensions of rootedness, appropriation, regeneration, at-easeness, and warmth. Using this framework observations were made in two libraries using categories relating to “homeness.” It was found that students do act and feel at home in the library. Newer library designs did not facilitate homeness more than older designs. It is concluded that new library designs have the opportunity to make students feel at home by offering flexible spaces to make their own, places to retreat from their desk, and basic amenities
High intensity tapping regime in a frustrated lattice gas model of granular compaction
In the frame of a well established lattice gas model for granular compaction,
we investigate the high intensity tapping regime where a pile expands
significantly during external excitation. We find that this model shows the
same general trends as more sophisticated models based on molecular dynamic
type simulations. In particular, a minimum in packing fraction as a function of
tapping strength is observed in the reversible branch of an annealed tapping
protocol.Comment: 5 pages, 4 figure
Eigenvalue density of Wilson loops in 2D SU(N) YM
In 1981 Durhuus and Olesen (DO) showed that at infinite N the eigenvalue
density of a Wilson loop matrix W associated with a simple loop in
two-dimensional Euclidean SU(N) Yang-Mills theory undergoes a phase transition
at a critical size. The averages of det(z-W), 1/det(z-W), and det(1+uW)/(1-vW)
at finite N lead to three different smoothed out expressions, all tending to
the DO singular result at infinite N. These smooth extensions are obtained and
compared to each other.Comment: 35 pages, 8 figure
Higher spin fields from a worldline perspective
Higher spin fields in four dimensions, and more generally conformal fields in
arbitrary dimensions, can be described by spinning particle models with a
gauged SO(N) extended supergravity on the worldline. We consider here the
one-loop quantization of these models by studying the corresponding partition
function on the one-dimensional torus. After gauge fixing the supergravity
multiplet, the partition function reduces to an integral over the corresponding
moduli space which is computed using orthogonal polynomial techniques. We
obtain a compact formula which gives the number of physical degrees of freedom
for all N in all dimensions. As an aside we compute the physical degrees of
freedom of the SO(4) = SU(2)xSU(2) model with only a SU(2) factor gauged, which
has attracted some interest in the literature.Comment: 21 page
From double Lie groupoids to local Lie 2-groupoids
We apply the bar construction to the nerve of a double Lie groupoid to obtain
a local Lie 2-groupoid. As an application, we recover Haefliger's fundamental
groupoid from the fundamental double groupoid of a Lie groupoid. In the case of
a symplectic double groupoid, we study the induced closed 2-form on the
associated local Lie 2-groupoid, which leads us to propose a definition of a
symplectic 2-groupoid.Comment: 23 pages, a few minor changes, including a correction to Lemma 6.
A method to calculate correlation functions for random matrices of odd size
The calculation of correlation functions for random matrix
ensembles, which can be carried out using Pfaffians, has the peculiar feature
of requiring a separate calculation depending on the parity of the matrix size
N. This same complication is present in the calculation of the correlations for
the Ginibre Orthogonal Ensemble of real Gaussian matrices. In fact the methods
used to compute the , N odd, correlations break down in the case of N
odd real Ginibre matrices, necessitating a new approach to both problems. The
new approach taken in this work is to deduce the , N odd correlations
as limiting cases of their N even counterparts, when one of the particles is
removed towards infinity. This method is shown to yield the correlations for N
odd real Gaussian matrices.Comment: 20 pages, corrected typo
Statistics of Coulomb blockade peak spacings for a partially open dot
We show that randomness of the electron wave functions in a quantum dot
contributes to the fluctuations of the positions of the conductance peaks. This
contribution grows with the conductance of the junctions connecting the dot to
the leads. It becomes comparable with the fluctuations coming from the
randomness of the single particle spectrum in the dot while the Coulomb
blockade peaks are still well-defined. In addition, the fluctuations of the
peak spacings are correlated with the fluctuations of the conductance peak
heights.Comment: 13 pages, 1 figur
Large N expansion of the 2-matrix model
We present a method, based on loop equations, to compute recursively all the
terms in the large topological expansion of the free energy for the
2-hermitian matrix model. We illustrate the method by computing the first
subleading term, i.e. the free energy of a statistical physics model on a
discretized torus.Comment: 41 pages, 9 figures eps
Statistics of Atmospheric Correlations
For a large class of quantum systems the statistical properties of their
spectrum show remarkable agreement with random matrix predictions. Recent
advances show that the scope of random matrix theory is much wider. In this
work, we show that the random matrix approach can be beneficially applied to a
completely different classical domain, namely, to the empirical correlation
matrices obtained from the analysis of the basic atmospheric parameters that
characterise the state of atmosphere. We show that the spectrum of atmospheric
correlation matrices satisfy the random matrix prescription. In particular, the
eigenmodes of the atmospheric empirical correlation matrices that have physical
significance are marked by deviations from the eigenvector distribution.Comment: 8 pages, 9 figs, revtex; To appear in Phys. Rev.
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