73,373 research outputs found

    Can lattice data for two heavy-light mesons be understood in terms of simply two-quark potentials?

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    By comparing lattice data for the two heavy-light meson system (Q^2 qbar^2) with a standard many-body approach employing only interquark potentials, it is shown that the use of unmodified two-quark potentials leads to a gross overestimate of the binding energy.Comment: Contribution to LATTICE99 (Heavy Quarks). 3 pages, 2 ps figure

    Performative regulation: a case study in how powerful people avoid criminal labels

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    This paper explores the role of invested powerful business actors in the criminalisation process as applied to the illicit antiquities market. We present a case study of the precise mechanics of the role played by trade interests in the formation of the Dealing in Cultural Objects (Offences) Act 2003. This process involved the trade’s entering appearance in the legislative process and neutralising the possible constraining effects on its members of the new criminal offence which was to be created. We begin by exploring the political, historical and economic context in which discussion of the terms of the 2003 Act first began. We then follow the Act from its genesis through its various stages of drafting and re-drafting, to its enactment. This case study of a single piece of legislation provides further data to add to the line of prior research that illustrates that powerful white-collar criminals, as well as sometimes preventing criminal legislation entering the statute books, can also influence the design of criminal legislation that does enter the statute books in order to protect themselves and their own business interests. We also use this case study of a process of contemporary law-making to outline the concept of performative regulation: broadly, that which in appearance serves political ends but in practice effects an inconsequential level of control

    The radial distributions of a heavy-light meson on a lattice

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    In an earlier work, the charge (vector) and matter (scalar) radial distributions of heavy-light mesons were measured in the quenched approximation on a 16^3 times 24 lattice with a quark-gluon coupling of 5.7, a lattice spacing of 0.17 fm, and a hopping parameter corresponding to a light quark mass about that of the strange quark. Several improvements are now made: 1) The configurations are generated using dynamical fermions with a quark-gluon coupling of 5.2 (a lattice spacing of 0.14 fm); 2) Many more gauge configurations are included (78 compared with the earlier 20); 3) The distributions at many off-axis, in addition to on-axis, points are measured; 4) The data-analysis is much more complete. In particular, distributions involving excited states are extracted. The exponential decay of the charge and matter distributions can be described by mesons of mass 0.9+-0.1 and 1.5+-0.1 GeV respectively - values that are consistent with those of vector and scalar qqbar-states calculated directly with the same lattice parameters.Comment: 3 pages, 4 figures, Lattice2002(heavyquark

    The law's interface with expanding technology

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    The role of the law in technology assessment is described in generalized terms of a legal system as it confronts expanding technology. The functions of a technology assessment are considered to be twofold; provide for legislative action designed to channel technological advance along lines which are regarded as optimal from the standpoint of society's interests; and encourage and promote legislative action which will deal decisively with the potential disruptions and injuries caused by technology at a much earlier stage of the growth of the technology than is feasible under the present legal system. It is concluded that since new law always has a disruptive effect on expectations and commitments arrived at under old law, it is generally desirable that new legislation should make the least possible change in the law consistant with accomplishing the desired objective

    A model for multi-quark systems

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    As a step towards understanding multi-quark systems abundant in nature we construct a model that reproduces the binding energies of static four-quark systems. These energies have been calculated using SU(2) lattice gauge theory for a set of six different geometries representative of the general case. The model is based on ground and excited state two-body potentials and multi-quark interaction terms.Comment: 10 pages, one LaTeX figur
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