2,675 research outputs found
Arguments towards the construction of a matrix model groundstate
We discuss the existence and uniqueness of wavefunctions for inhomogenoeus
boundary value problems associated to x^2y^2-type matrix model on a bounded
domain of R^2. Both properties involve a combination of the Cauchy-Kovalewski
Theorem and a explicit calculations.Comment: 3 pages, Latex Proceedings for the XIX Simposio Chileno de Fisica,
SOCHIFI 2014 Conference, 26-28 November 2014, held at Concepcion U., Chil
The supermembrane with central charges:(2+1)-D NCSYM, confinement and phase transition
The spectrum of the bosonic sector of the D=11 supermembrane with central
charges is shown to be discrete and with finite multiplicities, hence
containing a mass gap. The result extends to the exact theory our previous
proof of the similar property for the SU(N) regularised model and strongly
suggest discreteness of the spectrum for the complete Hamiltonian of the
supermembrane with central charges. This theory is a quantum equivalent to a
symplectic non-commutative super-Yang-Mills in 2+1 dimensions, where the
space-like sector is a Riemann surface of positive genus. In this context, it
is argued how the theory in 4D exhibits confinement in the N=1 supermembrane
with central charges phase and how the theory enters in the quark-gluon plasma
phase through the spontaneous breaking of the centre. This phase is interpreted
in terms of the compactified supermembrane without central charges.Comment: 33 pages, Latex. In this new version, several changes have been made
and various typos were correcte
On the groundstate of octonionic matrix models in a ball
In this work we examine the existence and uniqueness of the groundstate of a
SU(N)x G2 octonionic matrix model on a bounded domain of R^N. The existence and
uniqueness argument of the groundstate wavefunction follows from the
Lax-Milgram theorem. Uniqueness is shown by means of an explicit argument which
is drafted in some detail.Comment: Latex, 6 page
Massless ground state for a compact SU(2) matrix model in 4D
We show the existence and uniqueness of a massless supersymmetric ground
state wavefunction of a SU(2) matrix model in a bounded smooth domain with
Dirichlet boundary conditions. This is a gauge system and we provide a new
framework to analyze the quantum spectral properties of this class of
supersymmetric matrix models subject to constraints which can be generalized
for arbitrary number of colors.Comment: 12 pages, Latex. Somme clarifications. Minor changes. Version to
appear at NP
The ground state of the D=11 supermembrane and matrix models on compact regions
We establish a general framework for the analysis of boundary value problems
of matrix models at zero energy on compact regions. We derive existence and
uniqueness of ground state wavefunctions for the mass operator of the
regularized supermembrane theory, that is the supersymmetric
matrix model, on balls of finite radius. Our results rely on the
structure of the associated Dirichlet form and a factorization in terms of the
supersymmetric charges. They also rely on the polynomial structure of the
potential and various other supersymmetric properties of the system.Comment: Latex, 26 pages. We have added some comments at the introduction in
order to make it easier for the reader. Results of the paper unchange
Social Sensing of Floods in the UK
"Social sensing" is a form of crowd-sourcing that involves systematic
analysis of digital communications to detect real-world events. Here we
consider the use of social sensing for observing natural hazards. In
particular, we present a case study that uses data from a popular social media
platform (Twitter) to detect and locate flood events in the UK. In order to
improve data quality we apply a number of filters (timezone, simple text
filters and a naive Bayes `relevance' filter) to the data. We then use place
names in the user profile and message text to infer the location of the tweets.
These two steps remove most of the irrelevant tweets and yield orders of
magnitude more located tweets than we have by relying on geo-tagged data. We
demonstrate that high resolution social sensing of floods is feasible and we
can produce high-quality historical and real-time maps of floods using Twitter.Comment: 24 pages, 6 figure
On the spectrum of a matrix model for the D=11 supermembrane compactified on a torus with non-trivial winding
The spectrum of the Hamiltonian of the double compactified D=11 supermembrane
with non-trivial central charge or equivalently the non-commutative symplectic
super Maxwell theory is analyzed. In distinction to what occurs for the D=11
supermembrane in Minkowski target space where the bosonic potential presents
string-like spikes which render the spectrum of the supersymmetric model
continuous, we prove that the potential of the bosonic compactified membrane
with non-trivial central charge is strictly positive definite and becomes
infinity in all directions when the norm of the configuration space goes to
infinity. This ensures that the resolvent of the bosonic Hamiltonian is
compact. We find an upper bound for the asymptotic distribution of the
eigenvalues.Comment: 11 pages, LaTe
A new paradigm for improved co-ordination and efficacy of European biomedical research: taking diabetes as a model
Today, European biomedical and health-related research is insufficiently well funded and is fragmented, with no common vision, less-than-optimal sharing of resources, and inadequate support and training in clinical research. Improvements to the competitiveness of European biomedical research will depend on the creation of new infrastructures that must be dynamic and free of bureaucracy, involve all stakeholders and facilitate faster delivery of new discoveries from bench to bedside. Taking diabetes research as the model, a new paradigm for European biomedical research is presented, which offers improved co-ordination and common resources that will benefit both academic and industrial clinical research. This includes the creation of a European Council for Health Research, first proposed by the Alliance for Biomedical Research in Europe, which will bring together and consult with all health stakeholders to develop strategic and multidisciplinary research programmes addressing the full innovation cycle. A European Platform for Clinical Research in Diabetes is proposed by the Alliance for European Diabetes Research (EURADIA) in response to the special challenges and opportunities presented by research across the European region, with the need for common standards and shared expertise and dat
Non-abelian D=11 Supermembrane
We obtain a U(M) action for supermembranes with central charges in the Light
Cone Gauge (LCG). The theory realizes all of the symmetries and constraints of
the supermembrane together with the invariance under a U(M) gauge group with M
arbitrary. The worldvolume action has (LCG) N=8 supersymmetry and it
corresponds to M parallel supermembranes minimally immersed on the target M9xT2
(MIM2). In order to ensure the invariance under the symmetries and to close the
corresponding algebra, a star-product determined by the central charge
condition is introduced. It is constructed with a nonconstant symplectic
two-form where curvature terms are also present. The theory is in the strongly
coupled gauge-gravity regime. At low energies, the theory enters in a
decoupling limit and it is described by an ordinary N=8 SYM in the IR phase for
any number of M2-branes.Comment: Contribution to the Proceedings of the Dubna International SQS'09
Workshop ("Supersymmetries and Quantum Symmetries-2009", July 29 - August 3,
2009. 12pg, Late
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