887 resultados para Exponent of an Abelian Group
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Motivated by the description of the C*-algebra of the affine automorphism group N6,28 of the Siegel upper half-plane of degree 2 as an algebra of operator fields defined over the unitary dual View the MathML source of the group, we introduce a family of C*-algebras, which we call almost C0(K), and we show that the C*-algebra of the group N6,28 belongs to this class.
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Beyond Criminal Justice presents a vision of a future without brutal, authoritarian and repressive penal regimes. Many of the papers brought together here have been unavailable for more than two decades. Their republication indicates not only their continuing theoretical importance to abolitionist studies but also how they provide important insights into the nature and legitimacy of criminal processes in the here and now. Contributors highlight the human consequences of the harms of imprisonment, evidencing the hurt, injury and damage of penal incarceration across a number of different countries in Europe. Focusing on penal power and prisoner contestation to such power, the moral and political crises of imprisonment are laid bare. The contributors to Beyond Criminal Justice explore the urgent need for a coherent, rational and morally and politically sophisticated theoretical basis for penal abolitionism. Advocating a utopian imagination and at the same time practical solutions already implemented in countries around Europe - alongside grappling with controversial debates such as abolitionist responses to rape and sexual violence - the book steps outside of common sense assumptions regarding 'crime', punishment and 'criminal justice'. Beyond Criminal Justice will be of interest to students of criminology, zemiology, sociology, penology and critical legal studies as well as anyone interested in rethinking the problem of 'crime' and challenging the logic of the penal rationale.
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In order to analyze a unicellular-multicellular evolutionary transition, a multicellular organism is identified with the vector of viabilities and fecundities of its constituent cells. The Michod–Viossat–Solari–Hurand–Nedelcu index of group fitness for a multicellular organism is a function of these cell viabilities and fecundities. The MVSHN index has been used to analyze the germ-soma specialization and the fitness decoupling between the cell and organism levels that takes place during the transition to multicellularity. In this article, social choice theory is used to provide an axiomatic characterization of the group fitness ordering of vectors of cell viabilities and fecundities underlying the MVSHN index.
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In 1931 Dirac studied the motion of an electron in the field of a magnetic monopole and found that the quantization of electric charge can be explained by postulating the mere existence of a magnetic monopole. Since 1974 there has been a resurgence of interest in magnetic monopole due to the work of ‘t’ Hooft and Polyakov who independently observed that monopoles can exist as finite energy topologically stable solutions to certain spontaneously broken gauge theories. The thesis, “Studies on Magnetic Monopole Solutions of Non-abelian Gauge Theories and Related Problems”, reports a systematic investigation of classical solutions of non-abelian gauge theories with special emphasis on magnetic monopoles and dyons which possess both electric and magnetic charges. The formation of bound states of a dyon with fermions and bosons is also studied in detail. The thesis opens with an account of a new derivation of a relationship between the magnetic charge of a dyon and the topology of the gauge fields associated with it. Although this formula has been reported earlier in the literature, the present method has two distinct advantages. In the first place, it does not depend either on the mechanism of symmetry breaking or on the nature of the residual symmetry group. Secondly, the results can be generalized to finite temperature monopoles.
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The title compound is the first µ-η2-peroxodimetallic species to be characterised for a main group metal, possessing a long peroxo O–O bond, and large C–Sn–C angles, and is an unexpected product from the oxidation of [SnR2][R = CH(SiMe3)2], with a structure analogous to an organic ozonide.
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Escherichia coli O26:K60, with genetic attributes consistent with a potentially human enterohaemorrhagic E coli was isolated from the faeces of an eight-month-old heifer with dysentery. Attaching and effacing lesions were identified in the colon of a similarly affected heifer examined postmortem, and shown to be associated with E coli O26 by specific immunolabelling.
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Because reading groups historically have been under-researched (Long, 2003), the literature in this field is limited, presenting this as an interesting area for researchers. A need for further research is also explained by the fact that the traditional model of a reading group has been expanded through recent library policies leading to the development of specific group types such as groups for visually-impaired people (VIPs). To date, there have been no long-term empirical studies of these groups. This thesis, therefore, makes a significant contribution to the literature in this field by providing an in-depth exploration of a VIP reading group. The thesis is an ethnographic study which follows a library-run reading group for visually-impaired people from its formation in September 2007 and concentrates on five of the group members. The methodology for the study is influenced by participatory approaches to research involving disabled people by inviting the participants to participate in the co-creation of knowledge about themselves (French & Swain, 2000, p. 1). It is also influenced by new ethnography’s preference for multi-layered texts by exploring both the individual and collective experiences of the participants. While the participants are defined throughout as readers, visual-impairment plays a role in their experiences. I show that visually-impaired readers and reading groups sit within a complex web of factors which impact on their experiences both as individual readers and as a group. The study also shows that VIP reading groups challenge traditional definitions of reading as a visual activity. The study explores issues of power and concludes that, because ownership of the group lies with the library, this challenges the idea of reading groups empowering their members. Furthermore, offering discrete groups for visually-impaired readers means that the role these groups play in contributing to agendas for social inclusion is problematic. The study concludes by making suggestions as to how these groups might develop to be more inclusive and empowering.
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We extend the method of Cassels for computing the Cassels-Tate pairing on the 2-Selmer group of an elliptic curve, to the case of 3-Selmer groups. This requires significant modifications to both the local and global parts of the calculation. Our method is practical in sufficiently small examples, and can be used to improve the upper bound for the rank of an elliptic curve obtained by 3-descent.
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Let A be a finitely generated abelian group. We describe the automorphism group Aut(A) using the rank of A and its torsion part p-part A(p). For a finite abelian p-group A of type (k(1),..., k(n)), simple necessary and sufficient conditions for an n x n-matrix over integers to be associated with an automorphism of A are presented. Then, the automorphism group Aut(A) for a finite p-group A of type (k(1), k(2)) is analyzed. (C) 2008 Mathematical Institute Slovak Academy of Sciences.
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In this paper we study the spectrum of integral group rings of finitely generated abelian groups G from the scheme-theoretic viewpoint. We prove that the (closed) singular points of Spec Z[G], the (closed) intersection points of the irreducible components of Spec Z[G] and the (closed) points over the prime divisors of vertical bar t(G)vertical bar coincide. We also determine the formal completion of Spec Z[G] at a singular point.
Resumo:
Under p = c, we prove that it is possible to endow the free abelian group of cardinality c with a group topology that makes its square countably compact. This answers a question posed by Madariaga-Garcia and Tomita and by Tkachenko. We also prove that there exists a Wallace semigroup (i.e., a countably compact both-sided cancellative topological semigroup which is not a topological group) whose square is countably compact. This answers a question posed by Grant.
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The karyotype of a new species of Paratelmatobius from the P cardosoi group is described. As with other Paratelmatobius and Scythrophrys karyotypes, Paratelmatobius sp. (aff. cardosoi) shows a diploid number of 24 chromosomes, in addition to other similarities with the former karyotypes. The Paratelmatobius sp. (aff. cardosoi) karyotype differs from that of P. cardosoi in the morphology of pair 4, the NOR location and the C-bands in pairs 3 and 8 (exclusive to Paratelmatobius sp.) and those of pairs 7 and 9 (exclusive to P. cardosoi). Both karyotypes also differ in the amount of heterochromatin in pair 1. The presence of interstitial heterochromatin in the long arm of pair 1 and the interstitial C-bands in both arms of chromosome 5 are apparently synapomorphic characters of P. cardosoi and Paratelmatobius sp. (aff. cardosoi), since they are absent in the other Paratelmatobius and Scythrophrys karyotypes. In Paratelmatobius sp. (aff. cardosoi), the nucleolus organizer region is on the short arm of a small metacentric chromosome (pair 9), an arrangement similar to the NOR-bearing chromosome pair in the karyotype of P. poecilogaster and in karyotype 11 of Scythrophrys. A conspicuous heteromorphism unrelated to the sex determining mechanism was also observed and probably arose from a pericentric inversion.