88 research outputs found
Exotic prepotentials from D(-1)D7 dynamics
We compute the partition functions of D(-1)D7 systems describing the
multi-instanton dynamics of SO(N) gauge theories in eight dimensions. This is
the simplest instance of the so called exotic instantons. In analogy with the
Seiberg-Witten theory in four space-time dimensions, the prepotential and
correlators in the chiral ring are derived via localization formulas and found
to satisfy relations of the Matone type. Exotic prepotentials of SO(N) gauge
theories with N=2 supersymmetries in four-dimensions are also discussed.Comment: 19 page
Eco-labelling and product development: potentials and experiences
In this contribution, we concentrate on voluntary eco-labels, i.e., labels applied for reasons other than prescription by public regulation. Typical examples are the European eco-label, the Nordic White Swan or the German Blue Angel.
Section 2, The concept of eco-labelling, gives an overview of the history and âlandscapeâ of eco-labels. It provides information on countries using such a scheme, presents an important categorisation elaborated in this context, explains objectives and mechanisms and hints at the distinction between direct and indirect effects. Section 3,Eco-labelling and product development, refers to the potential and some experiences within business, i.e., on a micro-economic level. The following Section 4 Assessing the impacts presents an empirical view on the state, successes and failures of eco-labelling; primarily based on a meso- and macro-economic view. The final Section 5, Conclusions, deduces the consequences and challenges, both for business and policy, for strengthening eco-labelling
Instantons on Quivers and Orientifolds
We compute the prepotential for gauge theories descending from
SYM via quiver projections and mass deformations.
This accounts for gauge theories with product gauge groups and bifundamental
matter. The case of massive orientifold gauge theories with gauge group SO/Sp
is also described. In the case with no gravitational corrections the results
are shown to be in agreement with Seiberg-Witten analysis and previous results
in the literature.Comment: 28 pages, revised version, references added, some typos correcte
Multi instanton calculus on ALE spaces
We study SYM gauge theories living on ALE spaces.
Using localization formulae we compute the prepotential (and its
gravitational corrections) for SU(N) supersymmetric gauge
theories on ALE spaces of the type. Furthermore we derive the
Poincar\'{e} polynomial describing the homologies of the corresponding moduli
spaces of self-dual gauge connections. From these results we extract the partition function which is a modular form in agreement with the
expectations of duality.Comment: 26 pages, few explanations added. version to appear in nucl.phy
N=1 Superpotentials from Multi-Instanton Calculus
In this paper we compute gaugino and scalar condensates in N=1 supersymmetric
gauge theories with and without massive adjoint matter, using localization
formulae over the multi--instanton moduli space. Furthermore we compute the
chiral ring relations among the correlators of the theory and check
this result against the multi-instanton computation finding agreement.Comment: 31 pages, uses youngtab.sty, some explanations added, version to
appear in JHE
Instanton on toric singularities and black hole countings
We compute the instanton partition function for U(N) gauge
theories living on toric varieties, mainly of type
including or O_{\PP_1}(-p) surfaces. The results provide
microscopic formulas for the partition functions of black holes made out of
D4-D2-D0 bound states wrapping four-dimensional toric varieties inside a
Calabi-Yau. The partition function gets contributions from regular and
fractional instantons. Regular instantons are described in terms of symmetric
products of the four-dimensional variety. Fractional instantons are built out
of elementary self-dual connections with no moduli carrying non-trivial fluxes
along the exceptional cycles of the variety. The fractional instanton
contribution agrees with recent results based on 2d SYM analysis. The partition
function, in the large charge limit, reproduces the supergravity macroscopic
formulae for the D4-D2-D0 black hole entropy.Comment: 29 pages, 3 fig Section 5 is improved by the inclusion of a detailed
comparison between the instanton partition function and the D4-D2-D0 black
hole entropy formula coming from supergravit
Instantons and the 5D U(1) gauge theory with extra adjoint
In this paper we compute the partition function of 5D supersymmetric U(1)
gauge theory with extra adjoint matter in general -background. It is
well known that such partition functions encode very rich topological
information. We show in particular that unlike the case with no extra matter,
the partition function with extra adjoint at some special values of the
parameters directly reproduces the generating function for the Poincare
polynomial of the moduli space of instantons. Comparing our results with those
recently obtained by Iqbal et. al., who used the refined topological vertex
method, we present our comments on apparent discrepancies.Comment: 9 page
Stringy instanton corrections to N=2 gauge couplings
We discuss a string model where a conformal four-dimensional N=2 gauge theory
receives corrections to its gauge kinetic functions from "stringy" instantons.
These contributions are explicitly evaluated by exploiting the localization
properties of the integral over the stringy instanton moduli space. The model
we consider corresponds to a setup with D7/D3-branes in type I' theory
compactified on T4/Z2 x T2, and possesses a perturbatively computable heterotic
dual. In the heteoric side the corrections to the quadratic gauge couplings are
provided by a 1-loop threshold computation and, under the duality map, match
precisely the first few stringy instanton effects in the type I' setup. This
agreement represents a very non-trivial test of our approach to the exotic
instanton calculus.Comment: 63 pages, 5 figures. V2: final version with minor corrections
published on JHEP05(2010)10
Poincare polynomial of moduli spaces of framed sheaves on (stacky) Hirzebruch surfaces
We perform a study of the moduli space of framed torsion-free sheaves on
Hirzebruch surfaces by using localization techniques. We discuss some general
properties of this moduli space by studying it in the framework of
Huybrechts-Lehn theory of framed modules. We classify the fixed points under a
toric action on the moduli space, and use this to compute the Poincare
polynomial of the latter. This will imply that the moduli spaces we are
considering are irreducible. We also consider fractional first Chern classes,
which means that we are extending our computation to a stacky deformation of a
Hirzebruch surface. From the physical viewpoint, our results provide the
partition function of N=4 Vafa-Witten theory on total spaces of line bundles on
P1, which is relevant in black hole entropy counting problems according to a
conjecture due to Ooguri, Strominger and Vafa.Comment: 17 pages. This submission supersedes arXiv:0809.0155 [math.AG
Development of a taxonomy to describe massage treatments for musculoskeletal pain
BACKGROUND: One of the challenges in conducting research in the field of massage and bodywork is the lack of consistent terminology for describing the treatments given by massage therapists. The objective of this study was to develop a taxonomy to describe what massage therapists actually do when giving a massage to patients with musculoskeletal pain. METHODS: After conducting a review of the massage treatment literature for musculoskeletal pain, a list of candidate techniques was generated for possible inclusion in the taxonomy. This list was modified after discussions with a senior massage therapist educator and seven experienced massage therapists participating in a study of massage for neck pain. RESULTS: The taxonomy was conceptualized as a three level classification system, principal goals of treatment, styles, and techniques. Four categories described the principal goal of treatment (i.e., relaxation massage, clinical massage, movement re-education and energy work). Each principal goal of treatment could be met using a number of different styles, with each style consisting of a number of specific techniques. A total of 36 distinct techniques were identified and described, many of which could be included in multiple styles. CONCLUSION: A new classification system is presented whereby practitioners using different styles of massage can describe the techniques they employ using consistent terminology. This system could help facilitate standardized reporting of massage interventions
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