439 research outputs found
Solitons and giants in matrix models
We present a method for solving BPS equations obtained in the
collective-field approach to matrix models. The method enables us to find BPS
solutions and quantum excitations around these solutions in the one-matrix
model, and in general for the Calogero model. These semiclassical solutions
correspond to giant gravitons described by matrix models obtained in the
framework of AdS/CFT correspondence. The two-field model, associated with two
types of giant gravitons, is investigated. In this duality-based matrix model
we find the finite form of the -soliton solution. The singular limit of this
solution is examined and a realization of open-closed string duality is
proposed.Comment: 17 pages, JHEP cls; v2: final version to appear in JHEP, 2 references
added, physical motivation and interpretation clarifie
Multi-vortex solution in the Sutherland model
We consider the large- Sutherland model in the Hamiltonian
collective-field approach based on the expansion. The Bogomol'nyi limit
appears and the corresponding solutions are given by static-soliton
configurations. They exist only for \l<1, i.e. for the negative coupling
constant of the Sutherland interaction. We determine their creation energies
and show that they are unaffected by higher-order corrections. For \l=1, the
Sutherland model reduces to the free one-plaquette Kogut-Susskind model.Comment: Latex, using ioplppt.sty, 11 page
Collective Field Formulation of the Multispecies Calogero Model and its Duality Symmetries
We study the collective field formulation of a restricted form of the
multispecies Calogero model, in which the three-body interactions are set to
zero. We show that the resulting collective field theory is invariant under
certain duality transformations, which interchange, among other things,
particles and antiparticles, and thus generalize the well-known strong-weak
coupling duality symmetry of the ordinary Calogero model. We identify all these
dualities, which form an Abelian group, and study their consequences. We also
study the ground state and small fluctuations around it in detail, starting
with the two-species model, and then generalizing to an arbitrary number of
species.Comment: latex, 53 pages, no figures;v2-minor changes (a paragraph added
following eq. (61)
Efficacy of fentanyl transdermal patch in pain control after lower third molar surgery : a preliminary study
Surgical removal of impacted lower third molars is a common oral surgical procedure, generally followed by moderate to severe postoperative pain. Transdermal drug delivery as a concept offers interesting possibilities for postoperative pain control. The aim of this study was to evaluate the efficacy of transdermal system with fentanyl in relieving pain following impacted lower third molar surgery. Seventeen patients with bilateral impacted lower third molars were included in this preliminary study. For postoperative pain control, patients randomly received a fentanyl patch plus placebo tablet after the first operation and regular (placebo) patch and an analgesic, after the second operation. Analgesia was evaluated during first 24 hours postoperatively according to patients? reports about time of first pain appearance and additional analgesic consumption. Pain severity was rated using a 10 cm long visual analogue scale (VAS). Intensity of postoperative pain and postoperative analgesic consumption were significantly lower after the Fentanyl Transdermal System (FTS) was applied (p<0.05). Duration of postoperative analgesia was significantly higher with FTS when compared to control treatment (p<0.05). Based on the results of this preliminary study, transdermal system with fentanyl significantly reduced postoperative pain after third molar surgery
Waves and Solitons in the Continuum Limit of the Calogero-Sutherland Model
We examine a collection of particles interacting with inverse-square two-body
potentials in the thermodynamic limit. We find explicit large-amplitude density
waves and soliton solutions for the motion of the system. Waves can be
constructed as coherent states of either solitons or phonons. Therefore, either
solitons or phonons can be considered as the fundamental excitations. The
generic wave is shown to correspond to a two-band state in the quantum
description of the system, while the limiting cases of solitons and phonons
correspond to particle and hole excitations.Comment: Version to appear in Physical Rerview Letters; contains some new
results and explanation
Nonlinear laser scanning microscopy of oral multispecies-biofilms: Fixative induced fluorescence as a fast and economical in vitro screening method
In this letter we report a fast and easy method which could be used for initial screening of multispecies-biofilm development on putative new dental implant materials. Most staining methods require numerous washing steps that can result in detachment of loosely bound biofilms and therefore falsify the results. Thus, we used glutaraldehyde fixation, which induces autofluorescence through bacterial membrane protein cross-linking and concurrently stabilizes the biofilm structure. We analyzed the biofilms with nonlinear laser scanning microscopy and were able to (I) evaluate the multispecies-biofilm growth and (II) distinguish between bacterial species based on different two-photon autofluorescence intensities. © 2016 by De Gruyter
Density Correlation Functions in Calogero Sutherland Models
Using arguments from two dimensional Yang-Mills theory and the collective
coordinate formulation of the Calogero-Sutherland model, we conjecture the
dynamical density correlation function for coupling and , where is
an integer. We present overwhelming evidence that the conjecture is indeed
correct.Comment: 12 pages phyzzx, CERN-TH/94.7243 One reference change
Dynamics of electron emission in double photoionization processes near the Krypton 3d threshold
Two electron emission following photoabsorption near the Kr 3d threshold is investigated both experimentally and theoretically. On the experimental side, electron/electron coincidences using a magnetic bottle time of flight spectrometer allow us to observe the complete Double Photo Ionisation (DPI) continua of selected Kr2+ final states, and to see how these continua are affected by resonant processes in the vicinity of the Kr 3d threshold. The analysis is based on a quantum mechanical approach that takes into account the contribution of three different processes: A) Auger decay of the inner 3d vacancy with the associated post collision interaction (PCI) effects, B) capture of slow photoelectrons into discrete states followed by valence multiplet decay (VMD) of the excited ionic states and C) valence shell DPI. The dominant process for each Kr2+(4p-2) final state is the photoionization of the inner shell followed by Auger decay of the 3d vacancies. Moreover, for the 4p2(3P) and 4p-2(1D) final ionic states an important contribution comes from the processes of slow photoelectron capture followed by VMD as well as from double ionization of the outer shell involving also VMD
SELF-DUAL ANYONS IN UNIFORM BACKGROUND FIELDS
We study relativistic self-dual Chern-Simons-Higgs systems in the presence of
uniform background fields that explicitly break CTP. A rich, but discrete
vacuum structure is found when the gauge symmetry is spontaneously broken,
while the symmetric phase can have an infinite vacuum degeneracy at tree level.
The latter is due to the proliferation of neutral solitonic states that cost
zero energy. Various novel self-dual solitons, such as these, are found in both
the symmetric and the asymmetric phases. Also by considering a similar system
on a two-sphere and the subsequent large sphere limit, we isolate sensible and
finite expressions for the conserved angular and linear momenta, which satisfy
anomalous commutation relations. We conclude with a few remarks on unresolved
issues.Comment: LaTeX, 20 pages, 4 uuencoded figures included
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