315 research outputs found
Special limits and non-relativistic solutions
We study special vanishing horizon limit of `boosted' black D3-branes having
a compact light-cone direction. The type IIB solution obtained by taking such a
zero temperature limit is found to describe a nonrelativistic system with
dynamical exponent 3. We discuss about such limits in M2-branes case also.Comment: 10 pages; V2: various changes in interpretations including title; no
change in mathematical results, V3: minor font typo in eq.(7) remove
Galilean type IIA backgrounds and a map
We obtain non-relativistic AdS4 X CP3 solutions with dynamical exponent 3 in
type IIA string theory, both with and without Romans mass. The
compactifications to four dimensions are found to describe Proca fields in
anti-de Sitter spacetime. This leads us to conclude that the massive and
massless IIA theories should be identified in four dimensions and the Romans
mass should be identified with the `flux' along CP3 in a definite manner. From
supergravity point of view, it is suggestive of some four-dimensional symmetry
that rotates Romans mass into the flux along CP3. We also provide M-theory
Galilean ABJM background which gives rise to the nonrelativistic type IIA
solution.Comment: 10 pages;v2: major revisions, errors on supersymmetry corrected and
references added; to be published in MPL
Performance of 4 Pre-Trained Sentence Transformer Models in the Semantic Query of a Systematic Review Dataset on Peri-Implantitis
Systematic reviews are cumbersome yet essential to the epistemic process of medical science. Finding significant reports, however, is a daunting task because the sheer volume of published literature makes the manual screening of databases time-consuming. The use of Artificial Intelligence could make literature processing faster and more efficient. Sentence transformers are groundbreaking algorithms that can generate rich semantic representations of text documents and allow for semantic queries. In the present report, we compared four freely available sentence transformer pre-trained models (all-MiniLM-L6-v2, all-MiniLM-L12-v2, all-mpnet-base-v2, and All-distilroberta-v1) on a convenience sample of 6110 articles from a published systematic review. The authors of this review manually screened the dataset and identified 24 target articles that addressed the Focused Questions (FQ) of the review. We applied the four sentence transformers to the dataset and, using the FQ as a query, performed a semantic similarity search on the dataset. The models identified similarities between the FQ and the target articles to a varying degree, and, sorting the dataset by semantic similarities using the best-performing model (all-mpnet-base-v2), the target articles could be found in the top 700 papers out of the 6110 dataset. Our data indicate that the choice of an appropriate pre-trained model could remarkably reduce the number of articles to screen and the time to completion for systematic reviews
Holographic flows to IR Lifshitz spacetimes
Recently we studied `vanishing' horizon limits of `boosted' black D3-brane
geometry \cite{hsnr}. The type IIB solutions obtained by taking these special
double limits were found to describe nonrelativistic Lifshitz spacetimes at
zero temperature. In the present work we study these limits for TsT black-hole
solutions which include -field. The new Galilean solutions describe a
holographic RG flow from Schr\"odinger () spacetime in UV to a Lifshitz
universe () in the IR.Comment: 10 pages; v2: A bad typo in eq.8 corrected; v3: Discussion and
reference on Kaigorodov spaces included, correction in sec-3, to be published
in JHE
Universal scaling properties of extremal cohesive holographic phases
We show that strongly-coupled, translation-invariant holographic IR phases at
finite density can be classified according to the scaling behaviour of the
metric, the electric potential and the electric flux introducing four critical
exponents, independently of the details of the setup. Solutions fall into two
classes, depending on whether they break relativistic symmetry or not. The
critical exponents determine key properties of these phases, like thermodynamic
stability, the (ir)relevant deformations around them, the low-frequency scaling
of the optical conductivity and the nature of the spectrum for electric
perturbations. We also study the scaling behaviour of the electric flux through
bulk minimal surfaces using the Hartnoll-Radicevic order parameter, and
characterize the deviation from the Ryu-Takayanagi prescription in terms of the
critical exponents.Comment: v4: corrected a typo in eqn (3.29), now (3.28). Conclusions unchange
Lifshitz/Schr\"odinger D-p-branes and dynamical exponents
We extend our earlier study of special double limits of `boosted'
black hole solutions to include all black D-branes of type II strings. We
find that Lifshitz solutions can be obtained in generality, with varied
dynamical exponents, by employing these limits. We then study such double
limits for `boosted' D-brane bubble solutions and find that the resulting
non-relativistic solutions instead describe Schr\"odinger like spacetimes,
having varied dynamical exponents. We get a simple map between these Lifshitz &
Schr\"odinger solutions and a relationship between two types of dynamical
exponents. We also discuss about the singularities of the Lifshitz solutions
and an intriguing thermodynamic duality.Comment: 20 pages; 3 figures; v3: similar to JHE
Schr\"odinger Deformations of AdS_3 x S^3
We study Schr\"odinger invariant deformations of the AdS_3 x S^3 x T^4 (or
K3) solution of IIB supergravity and find a large class of solutions with
integer and half-integer dynamical exponents. We analyze the supersymmetries
preserved by our solutions and find an infinite number of solutions with four
supersymmetries. We study the solutions holographically and find that the dual
D1-D5 (or F1-NS5) CFT is deformed by irrelevant operators of spin one and two.Comment: 23 page
Holography for chiral scale-invariant models
Deformation of any d-dimensional conformal field theory by a constant null
source for a vector operator of dimension (d + z -1) is exactly marginal with
respect to anisotropic scale invariance, of dynamical exponent z. The
holographic duals to such deformations are AdS plane waves, with z=2 being the
Schrodinger geometry. In this paper we explore holography for such chiral
scale-invariant models. The special case of z=0 can be realized with gravity
coupled to a scalar, and is of particular interest since it is related to a
Lifshitz theory with dynamical exponent two upon dimensional reduction. We show
however that the corresponding reduction of the dual field theory is along a
null circle, and thus the Lifshitz theory arises upon discrete light cone
quantization of an anisotropic scale invariant field theory.Comment: 62 pages; v2, published version, minor improvements and references
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A retrospective study on periodontal disease progression in private practice
No specific funding was obtained for this study
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