Showing papers on "Unitary state published in 1990"
TL;DR: The authors argue that the notion of multiple semantics does not represent a theory of semantic organisation but is, instead, an arbitrary conjunction of a set of independent assumptions which are either unmotivated or, if motivated, equally compatible with a unitary semantics hypothesis.
Abstract: In this paper we discuss the issue of multiple versus unitary semantics. We argue that the notion of multiple semantics (as currently articulated) does not, in fact, represent a theory of semantic organisation but is, instead, an arbitrary conjunction of a set of independent assumptions which are either unmotivated or, if motivated, equally compatible with a unitary semantics hypothesis. Furthermore, the empirical evidence that has been cited as support for this hypothesis is equally compatible with variants of the unitary semantics hypothesis. A model of semantic processing—the Organised Unitary Content Hypothesis (O.U.C.H.)—that is able to account for reported patterns of dissociation of performance is discussed briefly.
525 citations
Book•
01 Jan 1990
TL;DR: In this paper, the stable trace formula for unitary groups in three variables was developed and applied to obtain a classification of automorphic representations, which is the first case in which the stable traces formula has been worked out beyond the case of SL (2) and related groups.
Abstract: The purpose of this book is to develop the stable trace formula for unitary groups in three variables. The stable trace formula is then applied to obtain a classification of automorphic representations. This work represents the first case in which the stable trace formula has been worked out beyond the case of SL (2) and related groups. Many phenomena which will appear in the general case present themselves already for these unitary groups.
268 citations
TL;DR: In this article, a generalized Korteweg-de Vries flow framework is used to compute correlation functions in unitary minimal models coupled to gravity, and a generalization to the Z2 orbifold D series case is given.
82 citations
77 citations
TL;DR: In this paper, the r-modular Brauer character of the special unitary groups SU(3, q2) for odd primes r not dividing q is studied.
Abstract: The purpose of this paper is to study the r-modular Brauer character of the special unitary groups SU(3, q2) for odd primes r not dividing q. It turns out that we encounter unexpected difficulties in the principal r-block in the case r‖q + 1. Some ways are described how to attack this problem, which are at least sufficient to solve the problem for an infinite number of prime powers q.
71 citations
TL;DR: In this article, a series of unitary representations of the quantum group SU q (1, 1) are introduced and their matrix elements are expressed in terms of the basic hypergeometric functions.
Abstract: Some series of unitary representations of the quantum group SU q (1, 1) are introduced. Their matrix elements are expressed in terms of the basic hypergeometric functions. Operator realization of the coordinate elements of SU q (1, 1) and aq-analogue of some classical identities are discussed.
63 citations
TL;DR: The original institutional design of Dutch administration and intergovernmental relations is commonly referred to as the ‘decentralized unitary state’ as discussed by the authors, which emphasized interdependence, diversity and the dynamic interaction of relatively independent layers of government.
Abstract: The original institutional design of Dutch administration and intergovernmental relations is commonly referred to as the ‘decentralized unitary state’. However, the views of traditional administrative theorists have been misrepresented. Hierarchy, uniformity and the separation and delimitation of layers of government are not, as often alleged, the theoretical underpinnings of the Dutch unitary state. Rather, classical theory emphasized interdependence, diversity and the dynamic interaction of relatively independent layers of government. This image suggests that Dutch administration does not need a greater separation of layers of government but better means for regulating conflict. It also suggests that the unitary state comes in several guises and cannot be equated with a monocentric system of government.
42 citations
TL;DR: In this article, a quasi-systematic investigation of the Virasoro master equation is presented, where the space of all affine-Virasoro constructions is organized by K-conjugation into affine Voronoi nests, and an estimate of the dimension of the space is given.
Abstract: We report a quasi-systematic investigation of the Virasoro master equation. The space of all affine-Virasoro constructions is organized by K-conjugation into affine-Virasoro nests, and an estimate of the dimension of the space shows that most solutions await discovery. With consistent ansatze for the master equation, large classes of new unitary nests are constructed, including 1) quadratic deformation nests with continuous conformal weights, and 2) unitary irrational central charge nests, which may dominate unitary rational central charge on compact g.
40 citations
TL;DR: There is a connection between parallel transport on the Hilbert tensor product ℋ⊗ℋ (or equivalently, the space of Hilbert-Schmidt operators), the elements of which represent density matrices up to unitary operators as discussed by the authors.
Abstract: There is a natural connection and parallel transport on the Hilbert tensor product ℋ⊗ℋ (or, equivalently, the space of Hilbert-Schmidt operators), the elements of which represent density matrices in ℋ up to unitary operators. We postulate a time evolution equation, which leads to this connection after extracting a proper ‘dynamical’ unitary phase. As an example, we compute the holonomy of a loop of temperature states for the spin in a rotating magnetic field.
TL;DR: In this paper, rank is defined for unitary representations of general linear groups over a locally compact, nondiscrete field, and it is shown how rank determines to a large extent the asymptotic behavior of matrix coefficients of the representations.
Abstract: A notion of rank for unitary representations of general linear groups over a locally compact, nondiscrete field is defined. Rank measures how singular a representation is, when restricted to the unipotent radical of a maximal parabolic subgroup. Irreducible representations of small rank are classified. It is shown how rank determines to a large extent the asymptotic behavior of matrix coefficients of the representations. I. DEFINITION AND BASIC PROPERTIES OF RANK 0. INTRODUCTION The unitary dual of GLn (F), F a locally compact nondiscrete field, has been classified by D. Vogan [V] in the Archimedean case, and, up to the construction of all cuspidal representations, by M. Tadic in the non-Archimedean case. Much remains to be done, however, in terms of the study of specific properties of the unitary representations involved. The inspiration for this paper comes form the following well-known theorem of Howe and Moore. Theorem 0.1 [HM]. Let G be a Zariski connected reductive algebraic group over a nondiscrete locally compact field F, and let p be a unitary representation of dimension greater than 1 such that the center Z of G acts by a character. Then the absolute values of the matrix coefficients of p approach zero at infinity on G/z. An easy consequence of this is Corollary 0.2. In the hypotheses for Theorem 0.1, if N is a subgroup of G which is not compact modulo Z, any vector that is invariant under N transforms according to a character of G. o In particular if p is irreducible and has a nontrivial N-invariant vector, p must be a character. Received by the editors August 15, 1988. 1980 Mathematics Subject Classification (1985 Revisiont). Primary 22E46, 22E50. This paper was submitted, in a different form, in partial fulfillment of the requirements for Doctor of Philosophy in the Department of Mathematics of Yale University. The author acknowledges support from the Consiglio Nazionale delle Ricerche, Italy. ( 1990 American Mathematical Society 0002-9947/90 $1.00 + $.25 per page
Journal Article•
TL;DR: The case against privatisation of health care is buttressed by moral, economic and sociological justification for developing a unitary national health service/insurance system.
Abstract: Medicine throughout the world is facing many critical challenges. In South Africa these are exacerbated by the effects apartheid has had on the structure, funding, distribution and delivery of health care. The demographic, economic, political, ethical and management problems facing our health services and the arguments in favour of privatisation are briefly reviewed. The case against privatisation of health care is buttressed by moral, economic and sociological justification for developing a unitary national health service/insurance system. In a rapidly changing South Africa medical care could become the leading edge of an enlightened social policy, which may facilitate peaceful progress towards a better future for all in our country and sub-continent.
TL;DR: In this paper, a high-level expansion of the Virasoro master equation is developed as a tool for the systematic study of affine-Virasoro space, which is applied to see all the (high-k smooth) unitary solutions on SU(3) in the basic ansatz.
Book•
01 Jan 1990
TL;DR: For strongly coupled 2D-gravity, with central charge Cgrav = 1 +6(s + 2), s = 0, ± 1 a chiral (2, 2)-operator satisfies a closed exchange algebra on the unit circle with a consistent restriction to a unitary subspace of the Virasoro representation as discussed by the authors.
TL;DR: In this paper, the Jordan-Schwinger representations of the groups under consideration are discussed based on the mixed sets of creation and annihilation operators of boson or fermion type.
Abstract: The unitary Cayley–Klein groups are defined as the groups that are obtained by the contractions and analytical continuations of the special unitary groups. The Jordan–Schwinger representations of the groups under consideration are discussed based on the mixed sets of creation and annihilation operators of boson or fermion type. The matrix elements of finite group transformations are obtained in the bases of coherent states.
TL;DR: In this article, the authors characterized linear isometries on Hn with respect to a unitary similarity invariant norm and obtained a related result concerning the characterization of those linear operators which preserve the set of matrices whose vectors of eigenvalues belong to a certain compact subset of is also obtained.
Abstract: A norm N(·) on Hn the space of all n × n hermitian matrices, is unitary similarity invariant if N(UAU* ) = N(A) for all hermitian matrices A and all unitary matrices U. We characterize those linear isometries on Hn with respect to a unitary similarity invariant norm. A related result concerning the characterization of those linear operators on Hn which preserve the set of matrices whose vectors of eigenvalues belong to a certain compact subset of is also obtained.
Book•
21 Sep 1990
TL;DR: In this paper, the authors investigated unitary matrix models in the scaling limit using the method of orthogonal polynomials on the unit circle and showed that string equations belong to the same univesality class as equations obtained from Hermitian matrix models.
Abstract: We investigate unitary matrix models in the scaling limit using the method of orthogonal polynomials on the unit circle. We show that, f or a certain choice of coupling constants, string equations belong to the same univesality class as equations obtained from Hermitian matrix models. In addition, we show how a new class of string equations emerges as a consequence of the compactness of the unitary groups.
Journal Article•
TL;DR: In this article, a unitary Lie superalgebra is constructed from the basis elements of a Clifford algebra Cl n and the authors generate a grading leading to unitary superalgebras when n is even.
Abstract: From the basis elements of a Clifford algebra Cl n the authors generate a grading leading to a unitary Lie superalgebra when n is even. Such a construction is motivated by the understanding of the specific properties of the fermionic variables in the so-called spin-orbit coupling procedure of supersymmetrisation in N=2 supersymmetric quantum mechanics. The n-odd case is also considered and some specific examples are discussed.
TL;DR: The model is shown to be singular, and this disproves a conjecture put forward by Gotay and Demaret to the effect that unitary quantum dynamics in a slow-time'' gauge is always nonsingular.
Abstract: An example of a quantum cosmological model is presented whose dynamics is unitary although the time-dependent Hamiltonian operator fails to be self-adjoint (because it is not defined) for a particular value of {ital t}. The model is shown to be singular, and this disproves a conjecture put forward by Gotay and Demaret to the effect that unitary quantum dynamics in a slow-time'' gauge is always nonsingular.
CERN1
TL;DR: In this article, it was shown that minimal models coupled to 2D gravity have a finite number of physical states corresponding to their non-null primary fields, assuming that Liouville primaries with given conformal weight have finite multiplicity.
TL;DR: For every commuting family of unitary operators in a π-k-space Πk there exists a non-positive subspace invariant under ℱ as discussed by the authors.
Abstract: In the present note we give a new and short proof of Naimark's theorem asserting that for every commuting family ℱ of unitary operators in a πk-space Πk there exists ak-dimensional, nonpositive subspace invariant under ℱ.