2,065 research outputs found
Globalization of Distinguished Supercuspidal Representations of GL(n)
No full textAn irreducible supercuspidal representation of = GL(n, ), where is a nonarchimedean local field of characteristic zero, is said to be “distinguished” by a subgroup of and a quasicharacter of if Hom(, ) ≠ 0. There is a suitable global analogue of this notion for an irreducible, automorphic, cuspidal representation associated to GL(n). Under certain general hypotheses, it is shown in this paper that every distinguished, irreducible, supercuspidal representation may be realized as a local component of a distinguished, irreducible automorphic, cuspidal representation. Applications to the theory of distinguished supercuspidal representations are provided
Restriction of Representations of GL (n + 1, ℂ) to GL (n, ℂ) and Action of the Lie Overalgebra
No full textConsider a restriction of an irreducible finite dimensional holomorphic representation of GL(n+1,C) to the subgroup GL(n,C). We write explicitly formulas for generators of the Lie algebra gl(n+1) in the direct sum of representations of GL(n,C). Nontrivial generators act as differential-difference operators, the differential part has order n − 1, the difference part acts on the space of parameters (highest weights) of representations. We also formulate a conjecture about unitary principal series of GL(n,C).© The Author(s) 201
The Balanced Voronoi Formulas for
No full textAbstract
In this article, we show how the Voronoi summation formula of [13] can be rewritten to incorporate hyper-Kloosterman sums of various dimensions on both sides. This generalizes a formula for with ordinary Kloosterman sums on both sides that was used in [1] to prove nonvanishing of GL(4) -functions by GL(2)-twists, and later by the second-named author in [16].</jats:p
A puzzling event during the X-ray emission of the binary system GX 1+4
No full textWe report on a long X-ray observation of the the slow-rotating binary pulsar GX 1+4. BeppoSAX observed, in the 0.1-200 keV energy range, an event in which the source flux dropped for almost a day, and then recovered. During this event only the high-energy emission was found to be pulsed and the pulsations were shifted in phase of similar to 0.2. The spectrum during the event was well fitted by a Compton-reflection model. A broad iron line at similar to 6.55 keV was present outside of the event, where instead two narrow emission lines at similar to 6.47 and similar to 7.05 keV were detected. The pulse profile was highly variable as a function of both energy and time. We interpret this low-flux event as an occultation of the direct X-ray emission, due to the increase of a torus-like accretion disk; we then discuss similarities between this source and the recently discovered highly absorbed INTEGRAL sources. (c) 2005 COSPAR. Published by Elsevier Ltd. All rights reserved
A Compton reflection dominated spectrum in a peculiar accreting neutron star
No full textWe report on a puzzling event that occurred during a long BeppoSAX observation of the slowly rotating binary pulsar GX 1+4. During this event, lasting about 1 d, the source X-ray flux was over a factor 10 lower than normal. The low-energy pulsations disappeared while at higher energies they were shifted in phase by similar to 0.25. The continuum spectrum taken outside this low-intensity event was well fitted by an absorbed cut-off power law and exhibited a broad iron line at similar to 6.5 keV probably due to the blending of the neutral (6.4 keV) and ionized (6.7 keV) K alpha iron lines. The spectrum during the event was Compton reflection dominated and it showed two narrow iron lines at similar to 6.4 and similar to 7.0 keV, the latter never revealed before in this source. We also present a possible model for this event in which a variation of the accretion rate thickens a torus-like accretion disc that hides for a while the direct neutron star emission from our line of sight. In this scenario, the Compton reflected emission observed during the event is well explained in terms of emission reflected by the side of the torus facing our line of sight
Special Bases of Irreducible Modules of the Quantized Universal Enveloping Algebra Uv(gl(n))
No full textAbstractIn this paper we construct a basis for an irreducible module of the quantized enveloping algebra Uv (gl(n)) which is a q-analogue of the special basis of an irreducible GL(n)-module introduced by C. de Concini and D. Kazhdan (Israel J. Math.40, 1980, 275-290). We conjecture the basis is the dual basis of the canonical basis introduced by G. Lusztig (J. Amer. Math. Soc.3, 1990, 447-498)
Bethe Vectors for Composite Models with gl(2|1) and gl(1|2) Supersymmetry
No full textSupersymmetric composite generalized quantum integrable models solvable by the algebraic Bethe ansatz are studied. Using a coproduct in the bialgebra of monodromy matrix elements and their action on Bethe vectors, formulas for Bethe vectors in the composite models with supersymmetry based on the super-Yangians Y[gl(2|1)] and Y[gl(1|2)] are derived.The author wants to express his gratitude to N.A. Slavnov for the proposal to investigate this
topic and discussions. He thanks also to S. Pakuliak for discussions and to A.P. Isaev and
C. Burd´ık for their support. The work of the author has been supported by the Grant Agency ˇ
of the Czech Technical University in Prague, grant No. SGS15/215/OHK4/3T/14, and by the
Grant of the Plenipotentiary of the Czech Republic at JINR, Dubna
External Powers in Latin America
No full textThis book examines the role of external powers in Latin America in the 21st century. Non-traditional partners have significantly increased their political and economic engagement with the continent. Five key questions arise: why has this surge taken place; when has it happened; in which regions and sectors is it mostly felt; what is the Latin American perspective; and what are the actual results? The book analyses 16 case studies: the United States, the European Union, China, Russia, Japan, Canada, India, Turkey, Iran, Israel, South Korea, Taiwan, Indonesia, the ASEAN countries, South Africa and Australia. The spectrum of existing explanations in the literature spans from neo-extractivism to South-South cooperation. This volume places them in context and proposes a more multifaceted approach, stressing a combination of systemic factors and internal dynamics both in Latin America and in the external partner countries. Geopolitics still matters and so do nation states, their interests and leaders. Ultimately, this surge in engagement has largely reproduced past patterns. Are new partners that different from the old ones
Combinatorial results on (1,2,1,2)-avoiding -orbit closures on
No full text35 pages, 18 figuresInternational audienceUsing recent results of the second author which explicitly identify the "-avoiding" -orbit closures on the flag manifold as certain Richardson varieties, we give combinatorial criteria for determining smoothness, lci-ness, and Gorensteinness of such orbit closures. (In the case of smoothness, this gives a new proof of a theorem of W.M. McGovern.) Going a step further, we also describe a straightforward way to compute the singular locus, the non-lci locus, and the non-Gorenstein locus of any such orbit closure. We then describe a manifestly positive combinatorial formula for the Kazhdan-Lusztig-Vogan polynomial in the case where corresponds to the trivial local system on a -avoiding orbit closure and corresponds to the trivial local system on any orbit contained in . This combines the aforementioned result of the second author, results of A. Knutson, the first author, and A. Yong, and a formula of Lascoux and Sch\"{u}tzenberger which computes the ordinary (type ) Kazhdan-Lusztig polynomial whenever is cograssmannian
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