Charged Conformal Killing Spinors

We study the twistor equation on pseudo-Riemannian $Spin^c-$manifolds whose solutions we call charged conformal Killing spinors (CCKS). We derive several integrability conditions for the existence of CCKS and study their relations to spinor bilinears. A construction principle for Lorentzian manifolds admitting CCKS with nontrivial charge starting from CR-geometry is presented. We obtain a partial classification result in the Lorentzian case under the additional assumption that the associated Dirac current is normal conformal and complete the Classification of manifolds admitting CCKS in all dimensions and signatures $\leq 5$ which has recently been initiated in the study of supersymmetric field theories on curved space.Comment: 26 pages v2: typos corrected, minor change

Conformal superalgebras via tractor calculus

We use the manifestly conformally invariant description of a Lorentzian conformal structure in terms of a parabolic Cartan geometry in order to introduce a superalgebra structure on the space of twistor spinors and normal conformal vector fields formulated in purely algebraic terms on parallel sections in tractor bundles. Via a fixed metric in the conformal class, one reproduces a conformal superalgebra structure which has been considered in the literature before. The tractor approach, however, makes clear that the failure of this object to be a Lie superalgebra in certain cases is due to purely algebraic identities on the spinor module and to special properties of the conformal holonomy representation. Moreover, it naturally generalizes to higher signatures. This yields new formulas for constructing new twistor spinors and higher order normal conformal Killing forms out of existing ones, generalizing the well-known spinorial Lie derivative. Moreover, we derive restrictions on the possible dimension of the space of twistor spinors in any metric signature.Comment: 36 page

Exclusive measurements for SUSY events with the ATLAS detector at the LHC

We present recent work performed in ATLAS on techniques used to reconstruct the decays of SUSY particles at the LHC. We concentrate on strategies to be applied to the first fb-1 of LHC data.Comment: ICHEP0

Baker's First-person Perspectives: They Are Not What They Seem

Lynne Baker's concept of a first-person perspective is not as clear and straightforward as it might seem at first glance. There is a discrepancy between her argumentation that we have first-person perspectives and some characteristics she takes first-person perspectives to have, namely, that the instances of this capacity necessarily persist through time and are indivisible and unduplicable. Moreover, these characteristics cause serious problems concerning personal identity

Wilson Loops in N=2 Superconformal Yang-Mills Theory

We present a three-loop O(g^6) calculation of the difference between the expectation values of Wilson loops evaluated in N=4 and superconformal N=2 supersymmetric Yang-Mills theory with gauge group SU(N) using dimensional reduction. We find a massive reduction of required Feynman diagrams, leaving only certain two-matter-loop corrections to the gauge field and associated scalar propagator. This "diagrammatic difference" leaves a finite result proportional to the bare propagators and allows the recovery of the zeta(3) term coming from the matrix model for the 1/2 BPS circular Wilson loop in the N=2 theory. The result is valid also for closed Wilson loops of general shape. Comments are made concerning light-like polygons and supersymmetric loops in the plane and on S^2.Comment: 16 pages. v2 minor changes, to appear in JHEP. v3 corrected reference

Emerging Constitutional Norms: Continuous Judicial Amendment of the Constitution—The Proportionality Test as a Moving Target

The so-called proportionality test of modifications to the Canadian Constitution are discussed. The Constitution is, at times, described as a moving target for change

Product differentiation in a spatial Cournot model with asymmetric demand

This paper considers a spatial discrimination Cournot model with asymmetric demand. We use the geographical interpretation of the linear market and introduce differentiated products. We analyze a location-quantity game and show that agglomeration or dispersed locations may arise, depending on parameter combinations. The degree of differentiation plays an important role in location choice if the demand is asymmetric. The higher the degree of differentiation between the products the more likely is agglomeration. Only cases with a low degree of differentiation and a relatively low difference in market size leads to the absence of agglomeration in the larger market.Spatial Cournot competition, Agglomeration, Asymmetric demand structure, Product differentiation

Status of the Florida soft crab industry

Florida Sea Grant, having been involved in the developnent of the Florida soft crab fishery since 1978, decided that an evaluation of the status of this fishery was necessary to determine to what extent Sea Grant Extension activities would be needed to further its development. To that end, this author, in cooperation with Florida Sea Grant marine extension agents and specialists, conducted a survey of the 1983 soft crab producers. Out of 28 identified blue crab shedding operations known to be producing soft shell crabs in 1983, 22 (78.6%) cooperated in filling out a fishery questionnaire which included sections describing their shedding facility, harvest methods, product types, production and sales data, and production costs. The reminder of this paper will be the findings of that survey. (12pp.