3,188 research outputs found

    The Iraq War: killing dreams of a unified EU?

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    For students of EU public policy, the EU's reaction during and after the Iraq War may represent the same story of impotence that has historically plagued the EU when trying to speak with a single voice and act with a united front during a major world crisis. Despite some achievements with the EU's Common and Foreign Security Policy (CFSP) of the early 1990s (Ginsberg 1997; Holland 1995), the Iraq War perhaps best reflects Cameron's concerns: "in handling serious political crises, especially those involving armed conflict, the Union has rarely acted as one", or acted effectively (Cameron, 1998, 66). Seeking to better understand why the EU did not act effectively during the Iraq War and to consider what lessons can be taken from this experience, the paper has three main objectives. First, the paper considers the theoretical reasons that help explain why the EU has historically failed to create a common defence and security policy. The section thereafter analyses developments during the Iraq war and tests which theoretical explanations (or combinations thereof) are of most value to understand the EU's stance. The final section then considers the future of the EU as an international actor in light of the fundamental concepts introduced by Hill (1993) regarding 'capabilities' and 'expectations' of EU foreign policy

    Equivariant map superalgebras

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    Suppose a group Γ\Gamma acts on a scheme XX and a Lie superalgebra g\mathfrak{g}. The corresponding equivariant map superalgebra is the Lie superalgebra of equivariant regular maps from XX to g\mathfrak{g}. We classify the irreducible finite dimensional modules for these superalgebras under the assumptions that the coordinate ring of XX is finitely generated, Γ\Gamma is finite abelian and acts freely on the rational points of XX, and g\mathfrak{g} is a basic classical Lie superalgebra (or sl(n,n)\mathfrak{sl}(n,n), n>0n > 0, if Γ\Gamma is trivial). We show that they are all (tensor products of) generalized evaluation modules and are parameterized by a certain set of equivariant finitely supported maps defined on XX. Furthermore, in the case that the even part of g\mathfrak{g} is semisimple, we show that all such modules are in fact (tensor products of) evaluation modules. On the other hand, if the even part of g\mathfrak{g} is not semisimple (more generally, if g\mathfrak{g} is of type I), we introduce a natural generalization of Kac modules and show that all irreducible finite dimensional modules are quotients of these. As a special case, our results give the first classification of the irreducible finite dimensional modules for twisted loop superalgebras.Comment: 27 pages. v2: Section numbering changed to match published version. Other minor corrections. v3: Minor corrections (see change log at end of introduction

    Extended T-systems

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    We use the theory of q-characters to establish a number of short exact sequences in the category of finite-dimensional representations of the quantum affine groups of types A and B. That allows us to introduce a set of 3-term recurrence relations which contains the celebrated T-system as a special case.Comment: 36 pages, latex; v2: version to appear in Selecta Mathematic

    On multigraded generalizations of Kirillov-Reshetikhin modules

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    We study the category of Z^l-graded modules with finite-dimensional graded pieces for certain Z+^l-graded Lie algebras. We also consider certain Serre subcategories with finitely many isomorphism classes of simple objects. We construct projective resolutions for the simple modules in these categories and compute the Ext groups between simple modules. We show that the projective covers of the simple modules in these Serre subcategories can be regarded as multigraded generalizations of Kirillov-Reshetikhin modules and give a recursive formula for computing their graded characters

    Faces of weight polytopes and a generalization of a theorem of Vinberg

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    The paper is motivated by the study of graded representations of Takiff algebras, cominuscule parabolics, and their generalizations. We study certain special subsets of the set of weights (and of their convex hull) of the generalized Verma modules (or GVM's) of a semisimple Lie algebra \lie g. In particular, we extend a result of Vinberg and classify the faces of the convex hull of the weights of a GVM. When the GVM is finite-dimensional, we ask a natural question that arises out of Vinberg's result: when are two faces the same? We also extend the notion of interiors and faces to an arbitrary subfield \F of the real numbers, and introduce the idea of a weak \F-face of any subset of Euclidean space. We classify the weak \F-faces of all lattice polytopes, as well as of the set of lattice points in them. We show that a weak \F-face of the weights of a finite-dimensional \lie g-module is precisely the set of weights lying on a face of the convex hull.Comment: Statement changed in Section 4. Typos fixed and some proofs updated. Submitted to "Algebra and Representation Theory." 18 page

    Continuity and change in party positions towards Europe in Italian parties: an examination of parties' manifestos

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    This paper analyses Italian parties' manifestos for national and European elections from 1979 to 1999 with the 'Wordscore' programme in order to gauge whether party positions with regard to the European Union have changed and whether the salience of the European Union has increased. Results indicate that, although there is no sign of increased salience, the leading Italian political parties have repositioned themselves in their attitudes towards the European Union, indicating that the European political space matters for national parties

    Policy Formulation, Implementation and Feedback in EU Merger Control

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    This paper analyses the formulation of the EU Merger Control Regulation (MCR) and its implementation via the 1992 Nestlé/Perrier merger. It offers two arguments. First, these phases of policy development occurred in ‘macro’ and ‘micro’ policy communities found at the supranational level of governance. The first community consists of larger Commission and business interests that formulated the MCR and the second of specific actors within the ‘macro’ community - the Merger Task Force and the firms – that implemented the rules. Secondly, the development of these communities can be explained by private interest theory. The conclusions highlight two main lessons for students of comparative European politics. First, the concept of ‘macro’ and ‘micro’ communities existing at both the formulation and implementation phases of policy offers a framework for comparativists to better analyse which types of actors will interact during different stages of the policy-making process. It is argued that while the (larger) ‘macro’ community helps define the nature of the regulations, a related, but not necessarily equally composed, ‘micro’ community eventually implements the rules, potentially changing the nature of the policy itself via a ‘feedback’ mechanism. Secondly, this study suggests that comparativists must pay more attention to the private interests of policy-makers and how these are intertwined with their ‘private fears.’ Such interests and fears guide policy-makers while simultaneously constrain them from acting alone.

    Representations of Double Affine Lie algebras

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    We study representations of the double affine Lie algebra associated to a simple Lie algebra. We construct a family of indecomposable integrable representations and identify their irreducible quotients. We also give a condition for the indecomposable modules to be irreducible, this is analogous to a result in the representation theory of quantum affine algebras. Finally, in the last section of the paper, we show, by using the notion of fusion product, that our modules are generically reducible

    N-enlarged Galilei Hopf algebra and its twist deformations

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    The N-enlarged Galilei Hopf algebra is constructed. Its twist deformations are considered and the corresponding twisted space-times are derived.Comment: 8 pages, no figure

    Twisted Quantum Fields on Moyal and Wick-Voros Planes are Inequivalent

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    The Moyal and Wick-Voros planes A^{M,V}_{\theta} are *-isomorphic. On each of these planes the Poincar\'e group acts as a Hopf algebra symmetry if its coproducts are deformed by twist factors. We show that the *-isomorphism T: A^M_{\theta} to A^V_{\theta} does not also map the corresponding twists of the Poincar\'e group algebra. The quantum field theories on these planes with twisted Poincar\'e-Hopf symmetries are thus inequivalent. We explicitly verify this result by showing that a non-trivial dependence on the non-commutative parameter is present for the Wick-Voros plane in a self-energy diagram whereas it is known to be absent on the Moyal plane (in the absence of gauge fields). Our results differ from these of (arXiv:0810.2095 [hep-th]) because of differences in the treatments of quantum field theories.Comment: 12 page
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