2,890 research outputs found
Toda lattice field theories, discrete W algebras, Toda lattice hierarchies and quantum groups
In analogy with the Liouville case we study the Toda theory on the
lattice and define the relevant quadratic algebra and out of it we recover the
discrete algebra. We define an integrable system with respect to the
latter and establish the relation with the Toda lattice hierarchy. We compute
the the relevant continuum limits. Finally we find the quantum version of the
quadratic algebra.Comment: 12 pages, LaTe
Hamiltonian structure and coset construction of the supersymmetric extensions of N=2 KdV hierarchy
A manifestly N=2 supersymmetric coset formalism is applied to analyse the
"fermionic" extensions of N=2 and KdV hierarchies. Both these
hierarchies can be obtained from a manifest N=2 coset construction. This coset
is defined as the quotient of some local but non-linear superalgebra by a
subalgebra. Three superextensions of N=2 KdV hierarchy are
proposed, among which one seems to be entirely new.Comment: 11 pages, Latex, a few modifications in the tex
Normal Bundles, Pfaffians and Anomalies
We deal with the problem of diffeomorphism anomaly in theories with branes.
In particular we thoroughly analyze the problem of the residual chiral anomaly
of a five-brane immersed in M-theory, paying attention to its global
formulation in the five-brane world-volume. We conclude that the anomaly can be
canceled by a {\it local} counterterm in the five-brane world-volume.Comment: 17 pages, Latex, sign convention changed, typos correcte
Two-matrix model and c=1 string theory
We show that the most general two--matrix model with bilinear coupling
underlies string theory. More precisely we prove that
constraints, a subset of the correlation functions and the integrable hierarchy
characterizing such two--matrix model, correspond exactly to the
constraints, to the discrete tachyon correlation functions and to the
integrable hierarchy of the string.Comment: 12 pages, LaTeX, SISSA 54/94/EP (misprints corrected
Abelian 3-form gauge theory: superfield approach
We discuss a D-dimensional Abelian 3-form gauge theory within the framework
of Bonora-Tonin's superfield formalism and derive the off-shell nilpotent and
absolutely anticommuting Becchi-Rouet-Stora-Tyutin (BRST) and anti-BRST
symmetry transformations for this theory. To pay our homage to Victor I.
Ogievetsky (1928-1996), who was one of the inventors of Abelian 2-form
(antisymmetric tensor) gauge field, we go a step further and discuss the above
D-dimensional Abelian 3-form gauge theory within the framework of BRST
formalism and establish that the existence of the (anti-)BRST invariant
Curci-Ferrari (CF) type of restrictions is the hallmark of any arbitrary p-form
gauge theory (discussed within the framework of BRST formalism).Comment: LaTeX file, 8 pages, Talk delivered at BLTP, JINR, Dubna, Moscow
Region, Russi
Matrix models without scaling limit
In the context of hermitean one--matrix models we show that the emergence of
the NLS hierarchy and of its reduction, the KdV hierarchy, is an exact result
of the lattice characterizing the matrix model. Said otherwise, we are not
obliged to take a continuum limit to find these hierarchies. We interpret this
result as an indication of the topological nature of them. We discuss the
topological field theories associated with both and discuss the connection with
topological field theories coupled to topological gravity already studied in
the literature.Comment: Latex, SISSA-ISAS 161/92/E
The (N,M)-th KdV hierarchy and the associated W algebra
We discuss a differential integrable hierarchy, which we call the (N, M)MW_N$ algebra. We show
that there exist M distinct reductions of the (N, M)--th KdV hierarchy, which
are obtained by imposing suitable second class constraints. The most drastic
reduction corresponds to the (N+M)--th KdV hierarchy. Correspondingly the W(N,
M) algebra is reduced to the W_{N+M} algebra. We study in detail the
dispersionless limit of this hierarchy and the relevant reductions.Comment: 40 pages, LaTeX, SISSA-171/93/EP, BONN-HE-46/93, AS-IPT-49/9
New Spinor Fields on Lorentzian 7-Manifolds
This paper deals with the classification of spinor fields according to the
bilinear covariants in 7 dimensions. The previously investigated Riemannian
case is characterized by either one spinor field class, in the real case of
Majorana spinors, or three non-trivial classes in the most general complex
case. In this paper we show that by imposing appropriate conditions on spinor
fields in 7d manifolds with Lorentzian metric, the formerly obtained
obstructions for new classes of spinor fields can be circumvented. New spinor
fields classes are then explicitly constructed. In particular, on 7-manifolds
with asymptotically flat black hole background, these spinors can define a
generalized current density which further defines a time Killing vector at the
spatial infinity.Comment: 13 pages, improved, to match the final version accepted in JHE
- …