5,910 research outputs found
A construction of N=2 and centerless N=4 superconformal fields via affine superalgebras
In this note we give a new construction of the N=2 superconformal algebra
using currents of the affine superalgebra and free bosonic
fields, and also the N=4 superconformal algebra without central charge in terms
of currents of and free bosonic fields. Arguments on
commutants and invariant subspaces are added.Comment: 20 pages, amslate
On complete reducibility for infinite-dimensional Lie algebras
In this paper we study the complete reducibility of representations of
infinite-dimensional Lie algebras from the perspective of the representation
theory of vertex algebras.Comment: 63 pages; the proof of Lemma 1.3.1 is change
KdV type hierarchies, the string equation and constraints
To every partition one can associate a vertex operator
realization of the Lie algebras and . Using this
construction we make reductions of the --component KP hierarchy, reductions
which are related to these partitions. In this way we obtain matrix KdV type
equations. Now assuming that (1) is a --function of the
--th reduced KP hierarchy and (2) satisfies a
`natural' string equation, we prove that also satisfies the vacuum
constraints of the algebra.Comment: 29 pages of amstex, Correction of some errors and 1 reference adde
Finite growth representations of infinite Lie conformal algebras
We classify all finite growth representations of all infinite rank
subalgebras of the Lie conformal algebra gc_1 that contain a Virasoro
subalgebra.Comment: 22 page
Ramond sector of superconformal algebras via quantum reduction
Quantum hamiltonian reduction of affine superalgebras is studied in the
twisted case. The Ramond sector of "minimal" superconformal W-algebras is
described in detail, the determinant formula is obtained. Extensive list of
examples includes all the simple Lie superalgebras of rank up to 2. The paper
generalizes the results of Kac and Wakimoto (math-ph/0304011) to the twisted
case.Comment: 50 pages, 8 figures; v2: examples added, determinant formula
derivation modified, section order change
Matrix realizations of exceptional superconformal algebras
We give a general construction of realizations of the contact superconformal
algebras and , and the exceptional superconformal algebra
as subsuperalgebras of matrices over a Weyl algebra of size , where and . We show that there is no such a realization for
, if .Comment: 17 pages, LaTeX, to be published in the Journal of Geometry and
Physic
Quantum Reduction for Affine Superalgebras
We extend the homological method of quantization of generalized
Drinfeld--Sokolov reductions to affine superalgebras. This leads, in
particular, to a unified representation theory of superconformal algebras.Comment: 33 pages, LaTe
The return of the bursts: Thermonuclear flashes from Circinus X-1
We report the detection of 15 X-ray bursts with RXTE and Swift observations
of the peculiar X-ray binary Circinus X-1 during its May 2010 X-ray
re-brightening. These are the first X-ray bursts observed from the source after
the initial discovery by Tennant and collaborators, twenty-five years ago. By
studying their spectral evolution, we firmly identify nine of the bursts as
type I (thermonuclear) X-ray bursts. We obtain an arcsecond location of the
bursts that confirms once and for all the identification of Cir X-1 as a type I
X-ray burst source, and therefore as a low magnetic field accreting neutron
star. The first five bursts observed by RXTE are weak and show approximately
symmetric light curves, without detectable signs of cooling along the burst
decay. We discuss their possible nature. Finally, we explore a scenario to
explain why Cir X-1 shows thermonuclear bursts now but not in the past, when it
was extensively observed and accreting at a similar rate.Comment: Accepted for publication in The Astrophysical Journal Letters. Tables
1 & 2 merged. Minor changes after referee's comments. 5 pages, 4 Figure
Finite conformal modules over the N=2,3,4 superconformal algebras
In this paper we continue the study of representation theory of formal
distribution Lie superalgebras initiated in q-alg/9706030. We study finite
Verma-type conformal modules over the N=2, N=3 and the two N=4 superconformal
algebras and also find explicitly all singular vectors in these modules. From
our analysis of these modules we obtain a complete list of finite irreducible
conformal modules over the N=2, N=3 and the two N=4 superconformal algebras.Comment: 36 pages, no figures, LaTeX forma
Dirac operators and the Very Strange Formula for Lie superalgebras
Using a super-affine version of Kostant's cubic Dirac operator, we prove a
very strange formula for quadratic finite-dimensional Lie superalgebras with a
reductive even subalgebra.Comment: Latex file, 25 pages. A few misprints corrected. To appear in the
forthcoming volume "Advances in Lie Superalgebras", Springer INdAM Serie
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