391 research outputs found

    INTERNATIONAL TENSIONS IN THE NORTH PACIFIC SEAFOOD INDUSTRY

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    International Relations/Trade,

    Did Processing Quota Damage Alaska Red King Crab Harvesters? Empirical Evidence

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    The Bering Sea and Aleutian Islands (BSAI) red king crab fisheries are managed with a controversial, market-based policy design, in which both individual transferable fishing and processing quotas are used. Despite the fact that the policy design maintains contestable markets, concern remains that the use of individual transferable processing quota (IPQ) damages harvesters who receive individual transferable fishing quota (IFQ). An integer, nonlinear optimization model that incorporates an empirically estimated, non-linear catch per unit effort function is developed to measure imputed IFQ values. The imputed quota values are based solely on harvesting efficiency in the absence of IPQs or potential wealth redistribution between sectors. Results are compared to a prerationalization optimization model and also to empirical quota trading prices in the presence of IPQs. This with and without analysis lends insight into whether and/or the extent to which IPQs damaged BSAI crab harvesters.Crab rationalization, IPQ, IFQ, imputed quota prices, harvesting efficiency., Environmental Economics and Policy, Public Economics, Q22, Q28, D61, C61, L78.,

    Extension of the Poincar\'e group with half-integer spin generators: hypergravity and beyond

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    An extension of the Poincar\'e group with half-integer spin generators is explicitly constructed. We start discussing the case of three spacetime dimensions, and as an application, it is shown that hypergravity can be formulated so as to incorporate this structure as its local gauge symmetry. Since the algebra admits a nontrivial Casimir operator, the theory can be described in terms of gauge fields associated to the extension of the Poincar\'e group with a Chern-Simons action. The algebra is also shown to admit an infinite-dimensional non-linear extension, that in the case of fermionic spin-3/23/2 generators, corresponds to a subset of a contraction of two copies of WB2_2. Finally, we show how the Poincar\'e group can be extended with half-integer spin generators for d3d\geq3 dimensions.Comment: 12 pages, no figures. Matches published versio

    Toward the Integration of Economics and Outdoor Recreation Management

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    The general theme of this bulletin is that improved management of public-sector recreational resources is a multidisciplinary task. To this end, we attempt to integrate elements of outdoor recreation management theory and economics. The bulletin is written for both resource managers and researchers. For the former, our intent is to emphasize the importance of being aware of economic implications-at least conceptually-of management actions that influence the character and availability of recreational opportunities. To researchers involved in developing recreation management theory, we draw attention to the parallel between recreation management theory and the traditional managerial economic model of the firm. To economists, particularly those involved in developing and applying nonmarket valuation techniques, we draw attention to the types of decisions faced by resource managers. We argue that the most important resource allocation issues are of the incremental variety, so nonmarket valuation should also yield incremental values. These values alone, however, are not sufficient economic input into rational public choice analysis. The missing link , or nexus, between outdoor recreation management theory and economic analysis is the integration of supply and demand, as called for by traditional managerial economics. Collaborative research to develop recreation supply response functions akin to agricultural production functions is an essential step that is missing from both literatures. Theoretical and applied work assume greater practical importance if they feed information into this broadened framework. It is our hope that this bulletin will bring the disciplines closer to that realization

    Limits of three-dimensional gravity and metric kinematical Lie algebras in any dimension

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    We extend a recent classification of three-dimensional spatially isotropic homogeneous spacetimes to Chern--Simons theories as three-dimensional gravity theories on these spacetimes. By this we find gravitational theories for all carrollian, galilean, and aristotelian counterparts of the lorentzian theories. In order to define a nondegenerate bilinear form for each of the theories, we introduce (not necessarily central) extensions of the original kinematical algebras. Using the structure of so-called double extensions, this can be done systematically. For homogeneous spaces that arise as a limit of (anti-)de Sitter spacetime, we show that it is possible to take the limit on the level of the action, after an appropriate extension. We extend our systematic construction of nondegenerate bilinear forms also to all higher-dimensional kinematical algebras.Comment: 52 pages, 2 figures, 11 tables; v2: matches published version, additional references added and incorporated referee suggestion

    Asymptotic structure of N=2\mathcal{N}=2 supergravity in 3D: extended super-BMS3_3 and nonlinear energy bounds

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    The asymptotically flat structure of N=(2,0)\mathcal{N}=(2,0) supergravity in three spacetime dimensions is explored. The asymptotic symmetries are spanned by an extension of the super-BMS3_3 algebra, with two independent u^(1)\hat{u}(1) currents of electric and magnetic type. These currents are associated to U(1)U(1) fields being even and odd under parity, respectively. Remarkably, although the U(1)U(1) fields do not generate a backreaction on the metric, they provide nontrivial Sugawara-like contributions to the BMS3_3 generators, and hence to the energy and the angular momentum. The entropy of flat cosmological spacetimes with U(1)U(1) fields then acquires a nontrivial dependence on the u^(1)\hat{u}(1) charges. If the spin structure is odd, the ground state corresponds to Minkowski spacetime, and although the anticommutator of the canonical supercharges is linear in the energy and in the electric-like u^(1)\hat{u}(1) charge, the energy becomes bounded from below by the energy of the ground state shifted by the square of the electric-like u^(1)\hat{u}(1) charge. If the spin structure is even, the same bound for the energy generically holds, unless the absolute value of the electric-like charge is less than minus the mass of Minkowski spacetime in vacuum, so that the energy has to be nonnegative. The explicit form of the Killing spinors is found for a wide class of configurations that fulfills our boundary conditions, and they exist precisely when the corresponding bounds are saturated. It is also shown that the spectra with periodic or antiperiodic boundary conditions for the fermionic fields are related by spectral flow, in a similar way as it occurs for the N=2\mathcal{N}=2 super-Virasoro algebra. Indeed, our super-BMS3_3 algebra can be recovered from the flat limit of the superconformal algebra with N=(2,2)\mathcal{N}=(2,2), truncating the fermionic generators of the right copy.Comment: 32 pages, no figures. Talk given at the ESI Programme and Workshop "Quantum Physics and Gravity" hosted by ESI, Vienna, June 2017. V3: minor changes and typos corrected. Matches published versio

    Revisiting the asymptotic dynamics of General Relativity on AdS3_3

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    The dual dynamics of Einstein gravity on AdS3_3 supplemented with boundary conditions of KdV-type is identified. It corresponds to a two-dimensional field theory at the boundary, described by a novel action principle whose field equations are given by two copies of the "potential modified KdV equation". The asymptotic symmetries then transmute into the global Noether symmetries of the dual action, giving rise to an infinite set of commuting conserved charges, implying the integrability of the system. Noteworthy, the theory at the boundary is non-relativistic and possesses anisotropic scaling of Lifshitz type.Comment: 18 page
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