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Chemical dependency treatment: An examination of following continuing care recommendations
The purpose of this study was to determine what influence scheduled phone contacts would have on the extent of follow-through of continuing care recommednations by participants after treatment. Continuing care recommendations associated with ongoing sobriety include going to another level of care (individual therapy, group therapy, outpatient treatment), attending twelve-step meetings and communicating with a sponsor. Continuing care recommendations are typically written and referred to as a continuing care plan
Holography and condensed matter
This is a short review of recent developments in the application of AdS/CFT
methods to some condensed matter problems. In particular we present the
holographic description of a local quantum critical state, related to
(non)-Fermi liquids and the strange metal, that appears in large N CFTs with a
gravity dual at finite density and zero temperature, and explore its properties
by probing it with fermionic operators. Further we discuss possible bosonic and
fermionic instabilities, leading to s-, p- or d-wave holographic
superconductors and "electron stars". Finally we present a realization of local
quantum criticality via an impurity problem.Comment: 11 pages, 4 figures; Contribution to the proceedings of the "XVII
European Workshop on String Theory 2011", Padova, Italy, 5-9 September 2011;
v2: ref adde
The gravitational redshift of boson stars
We investigate the possible gravitational redshift values for boson stars
with a self-interaction, studying a wide range of possible masses. We find a
limiting value of for stable boson star configurations.
We compare theoretical expectation with the observational capabilities in
several different wavebands, concluding that direct observation of boson stars
by this means will be extremely challenging. X-ray spectroscopy is perhaps the
most interesting possibility.Comment: 7 pages RevTeX file with five figures incorporated (uses RevTeX and
psfig
Charged Dilatonic Black Holes and their Transport Properties
We briefly explain the consistency conditions imposed on the effective
holographic theories, which are parameterized by two real exponents
that control the IR dynamics. The general scaling of DC
resistivity with temperature at low temperature and AC conductivity at low
frequency across the whole plane are explained. There is a
codimension-one region where the DC resistivity is linear in the temperature.
For massive carriers, it is shown that when the scalar operator is not the
dilaton, the DC resistivity scales as the heat capacity (and entropy) for
-dimensional systems. Regions are identified where the theory at finite
density is a Mott-like insulator. This contribution is based on arXiv:1005.4690
with emphasis on the transport properties of charged dilatonic black holes with
potential.Comment: 6 pages and 6 figures. Contribution to the proceedings of the XVIth
European Workshop on String Theory, Madrid, Spain, June 14-18 201
Holographic Wilsonian flows and emergent fermions in extremal charged black holes
We study holographic Wilsonian RG in a general class of asymptotically AdS
backgrounds with a U(1) gauge field. We consider free charged Dirac fermions in
such a background, and integrate them up to an intermediate radial distance,
yielding an equivalent low energy dual field theory. The new ingredient,
compared to scalars, involves a `generalized' basis of coherent states which
labels a particular half of the fermion components as coordinates or momenta,
depending on the choice of quantization (standard or alternative). We apply
this technology to explicitly compute RG flows of charged fermionic operators
and their composites (double trace operators) in field theories dual to (a)
pure AdS and (b) extremal charged black hole geometries. The flow diagrams and
fixed points are determined explicitly. In the case of the extremal black hole,
the RG flows connect two fixed points at the UV AdS boundary to two fixed
points at the IR AdS_2 region. The double trace flow is shown, both numerically
and analytically, to develop a pole singularity in the AdS_2 region at low
frequency and near the Fermi momentum, which can be traced to the appearance of
massless fermion modes on the low energy cut-off surface. The low energy field
theory action we derive exactly agrees with the semi-holographic action
proposed by Faulkner and Polchinski in arXiv:1001.5049 [hep-th]. In terms of
field theory, the holographic version of Wilsonian RG leads to a quantum theory
with random sources. In the extremal black hole background the random sources
become `light' in the AdS_2 region near the Fermi surface and emerge as new
dynamical degrees of freedom.Comment: 37 pages (including 8 pages of appendix), 10 figures and 2 table
Banishing AdS ghosts with a UV cutoff
A recent attempt to make sense of scalars in AdS with "Neumann boundary
conditions" outside of the usual BF-window
led to pathologies including (depending on the precise context) either IR
divergences or the appearance of ghosts. Here we argue that such ghosts may be
banished by imposing a UV cutoff. It is also possible to achieve this goal in
certain UV completions. An example is the above AdS theory with a radial cutoff
supplemented by particular boundary conditions on the cutoff surface. In this
case we explicitly identify a region of parameter space for which the theory is
ghost free. At low energies, this theory may be interpreted as the standard
dual CFT (defined with "Dirichlet" boundary conditions) interacting with an
extra scalar via an irrelevant interaction. We also discuss the relationship to
recent works on holographic fermi surfaces and quantum criticality.Comment: 20 pages, 9 figure
Georgene Faulkner Correspondence
Entries include brief biographical information and correspondence from Hoffman at Julian Messner, Inc., on Books for Young People stationery concerning the sentiment of the Maine State Library that the setting of Faulkner\u27s book, a Maine farm in the summer, qualifies her as a Maine author
Holographic non-relativistic fermionic fixed point by the charged dilatonic black hole
Driven by the landscape of garden-variety condensed matter systems, we have
investigated how the dual spectral function behaves at the non-relativistic as
well as relativistic fermionic fixed point by considering the probe Dirac
fermion in an extremal charged dilatonic black hole with zero entropy. Although
the pattern for both of the appearance of flat band and emergence of Fermi
surface is qualitatively similar to that given by the probe fermion in the
extremal Reissner-Nordstrom AdS black hole, we find a distinctly different low
energy behavior around the Fermi surface, which can be traced back to the
different near horizon geometry. In particular, with the peculiar near horizon
geometry of our extremal charged dilatonic black hole, the low energy behavior
exhibits the universal linear dispersion relation and scaling property, where
the former indicates that the dual liquid is a Fermi one while the latter
implies that the dual liquid is not exactly of Landau Fermi type
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