Top quark properties measurements at the LHC

Highlights of measurements of the properties of the top quark at the LHC are presented. The measurements probe a range of the properties of the top quark, including the structure of the $Wtb$ vertex, the top-Z coupling and the top-quark mass. The results are compared to Standard Model predictions and in some cases limits on physics beyond the Standard Model are also extracted in the context of effective field theory models. The measurements use data collected by the ATLAS and CMS experiments during pp collisions at a centre-of-mass energy of 8 or 13 TeV.Comment: On behalf of the ATLAS and CMS Collaborations. Proceedings for Rencontres de Moriond EW Interactions and Unified Theories 2017. 8 pages, 8 figure

Asymptotic First Eigenvalue Estimates for the Biharmonic Operator on a Rectangle

We find an asymptotic expression for the first eigenvalue of the biharmonic operator on a long thin rectangle. This is done by finding lower and upper bounds which become increasingly accurate with increasing length. The lower bound is found by algebraic manipulation of the operator, and the upper bound is found by minimising the quadratic form for the operator over a test space consisting of separable functions. These bounds can be used to show that the negative part of the groundstate is small.Comment: 27 pages, 4 diagrams, 2 table

A Riemannian Off-Diagonal Heat Kernel Bound for Uniformly Elliptic Operators

We find a Gaussian off-diagonal heat kernel estimate for uniformly elliptic operators with measurable coefficients acting on regions $\Omega\subseteq\real^N$, where the order $2m$ of the operator satisfies $N<2m$. The estimate is expressed using certain Riemannian-type metrics, and a geometrical result is established allowing conversion of the estimate into terms of the usual Riemannian metric on $\Omega$. Work of Barbatis is applied to find the best constant in this expression.Comment: 29 pages, 6 diagram

The Hardy-Rellich Inequality for Polyharmonic Operators

The Hardy-Rellich inequality given here generalizes a Hardy inequality of Davies (1984), from the case of the Dirichlet Laplacian of a region $\Omega\subseteq\real^N$ to that of the higher order polyharmonic operators with Dirichlet boundary conditions. The inequality yields some immediate spectral information for the polyharmonic operators and also bounds on the trace of the associated semigroups and resolvents.Comment: 19 pages, 2 diagram

On utility-based super-replication prices of contingent claims with unbounded payoffs

Consider a financial market in which an agent trades with utility-induced restrictions on wealth. For a utility function which satisfies the condition of reasonable asymptotic elasticity at $-\infty$ we prove that the utility-based super-replication price of an unbounded (but sufficiently integrable) contingent claim is equal to the supremum of its discounted expectations under pricing measures with finite {\it loss-entropy}. For an agent whose utility function is unbounded from above, the set of pricing measures with finite loss-entropy can be slightly larger than the set of pricing measures with finite entropy. Indeed, the former set is the closure of the latter under a suitable weak topology. Central to our proof is the representation of a cone $C_U$ of utility-based super-replicable contingent claims as the polar cone to the set of finite loss-entropy pricing measures. The cone $C_U$ is defined as the closure, under a relevant weak topology, of the cone of all (sufficiently integrable) contingent claims that can be dominated by a zero-financed terminal wealth. We investigate also the natural dual of this result and show that the polar cone to $C_U$ is generated by those separating measures with finite loss-entropy. The full two-sided polarity we achieve between measures and contingent claims yields an economic justification for the use of the cone $C_U$, and an open question

Multivariate Utility Maximization with Proportional Transaction Costs.

We present an optimal investment theorem for a currency exchange model with random and possibly discontinuous proportional transaction costs. The investor’s preferences are represented by a multivariate utility function, allowing for simultaneous consumption of any prescribed selection of the currencies at a given terminal date. We prove the existence of an optimal portfolio process under the assumption of asymptotic satiability of the value function. Sufficient conditions for asymptotic satiability of the value function include reasonable asymptotic elasticity of the utility function, or a growth condition on its dual function. We show that the portfolio optimization problem can be reformulated in terms of maximization of a terminal liquidation utility function, and that both problems have a common optimizer.Duality Theory; Lagrange Duality; Multivariate Utility Function; Asymptotic Satiability; Optimal Portfolio; Transaction Costs; Foreign Exchange Market;

The performance of economic institutions in a dynamic environment: air transport and telecommunications in Germany and Britain

Detailed case study material illustrates why the performance of two British national champions (British Airways and British Telecom respectively) was superior to that of their German counterparts (Lufthansa and Deutsche Telekom): beyond just the effects of privatisation, both the airline and telecommunications industries have been characterised by substantial technological and market change which has altered the parameters of competitive strategy. Under these new dynamic environmental conditions, the British institutional structure has out-performed the denser network of relationships within Germany. This paper seeks to develop a theory of Anglo-Saxon competitive advantage that is not predicated only on the allocative efficiency of free markets, but precisely on the notions of adaptive efficiency or dynamic efficiency of non-market organisational activities. In other words, the hypothesis is that under specified types of industry conditions, the adaptive or dynamic efficiency of Anglo-Saxon firms may be superior to that of firms in Northern Europe's industry-coordination economies. -- Eine Analyse von umfangreichem Fallstudienmaterial läßt erkennen, warum Leistungsfähigkeit und tatsächlich erzieltes Ergebnis der beiden britischen Spitzenunternehmen British Airways und British Telecom besser waren im Vergleich zu den entsprechenden deutschen Unternehmen Lufthansa und Deutsche Telekom: Neben den quasi automatisch auftretenden Wirkungen jeder Privatisierung waren die Luftfahrt- und Telekommunikationsbranchen durch tiefgreifende Änderungen der Technologien und der Märkte gekennzeichnet, wodurch die Kenngrößen für eine wettbewerbsorientierte Strategie geändert wurden. Unter diesen neuentstandenen, dynamisierten Umfeldbedingungen erwies sich die Institutionenstruktur Großbritanniens als dem dichteren Beziehungsnetzwerk in Deutschland überlegen. In diesem Papier sollen Elemente für eine Theorie über diesen angelsächsischen Wettbewerbsvorteil entwickelt werden, die nicht nur auf der Allokationseffizienz von freien Märkten basieren, sondern genau auf die Wahrnehmungen einer Anpassungseffizienz oder dynamischen Effizienz von nichtmarktlichen Aktivitäten unterschiedlicher Organisationen bezogen sind. In anderen Worten, es geht um die Hypothese, daß bei bestimmten, in einer Branche gerade herrschenden Bedingungskonstellationen, die Anpassungs- oder Reaktionseffizienz von angelsächsischen Unternehmen derjenigen von Unternehmen in den branchenkoordinierten Volkswirtschaften des nördlichen Europas überlegen ist.

Cathodoluminescence of shocked quartz at the Cretaceous-Tertiary boundary

Empirical studies have documented an association between rock type and the cathodoluminescence color of constituent quartz grains. Quartz from extrusive igneous sources luminesces uniform pale blue. Quartz from intrusive igneous and high-grade metamorphic rocks generally luminesces darker purple-blue, whereas quartz recrystallized under low-grade metamorphic conditions luminesces reddish-brown. Quartz grains in most sandstones luminesce a heterogeneous mixture of these colors because the grains were derived from a variety of ultimate source rocks. If shocked quartz found at the Cretaceous-Tertiary (K-T) boundary is volcanic in origin, its cathodoluminescence should be predominantly pale blue. Alternatively, quartz grains derived from bolide impact upon, and ejection of, mixed igneous, metamorphic, and sedimentary rocks should luminesce a variety of colors. Grain mounts of sand collected at the K-T boundary horizon from the Clear Creek North site in the Raton Basin, Colorado were examined. Shocked quartz luminesced a variety of colors and very few grains luminesced the pale blue color that is typical of volcanic quartz. It was concluded that the shocked quartz was derived from a petrologically diverse source region without substantial volcanic contribution. Most shocked grains apparently were derived from low-grade metamorphic rocks, with a slightly smaller contribution from high-grade metamorphic and intrusive igneous rocks. Rare quartz grains with brown-luminescing rims reflect a minor addition from detrital sedimentary sources. The apparent relative abundances of intrusive (and rare extrusive) igneous, metamorphic, and sedimentary ultimate source rocks suggested by CL colors of shock-deformed quartz at the K-T boundary is consistent with a crustal/supracrustal origin for the grains

A qualitative evaluation of home based contraceptive and sexual health care for teenage mothers

This paper reports on the findings from a qualitative study exploring the experiences of teenage mothers using a nurse-led, home-based contraceptive service designed to prevent repeat unplanned pregnancies. The aim was to understand if, and how the service was effective in equipping teenage mothers to make informed choices about contraception, thus preventing a second pregnancy. Unplanned teenage pregnancy remains a significant focus of health and social policy in the United Kingdom (UK). Despite the long-term pattern of declining conception rates, the UK continues to report higher rates than comparable countries elsewhere in Europe. Current estimates suggest that approximately one fifth of births amongst under 18’s are repeat pregnancies (Teenage Pregnancy Independent Advisory Group, 2009). Services that are designed to reduce second unplanned pregnancies are an important element in promoting teenage sexual health. However, there has been no UK research that explores this kind of service and the experiences of service users. We conducted a qualitative interview study. From 2013–2014 we interviewed 40 teenage mothers who had engaged with the nurse-led, home-based contraceptive service. The data demonstrates that the service was effective in preventing repeat pregnancies in a number of cases. Among the aspects of the service which were found to contribute to its effectiveness were privacy, convenience, flexibility, appropriately timed access, the non-judgemental attitude of staff and ongoing support