Quantum superspace representation of superconformal algebras

The action for a supersymmetrical point particle introduced in a recent analysis of superspace is shown to have superconformal symmetry when all dimensional parameters are set equal to zero. This fact enables us to construct explicit representations of the d = 3 superconformal groups OSp(N;4) and the d = 4 ones SU(N; 2,2) in both classical and quantum superspace.     

Modular geometry of superconformal field theory

Two-dimensional superconformal field theory is discussed as geometry on universal supermoduli space, generalizing the conformal case. The compactification divisor of supermoduli space consists of super-Riemann surfaces with spin and super nodes, which are expressed algebraically. The local behavior of the super partition function on universal supermoduli space is described.     

More about superconformal field theory. Hamiltonian formalism

The Hamiltonian formalism for theN=1,d=4 superconformal system is given. The first-order formalism is found by starting from the canonical covariant one. As the conformal supergravity is a higher-derivative theory, to analyze the second-order Hamiltonian formalism the Ostrogradski transformation is introduced to define canonical momenta.     

Super characters and chiral asymmetry in superconformal field theory

The super partition function of two-dimensional superconformal field theory on the super torus is analyzed. Its bottom component is the integer index of the Ramond representation. The top component measures chiral asymmetry in the Ramond sector. It is a sesquilinear form in the odd “super characters” of the Ramond algebra. Formulas for the characters are derived for the irreducible unitary highest weight representations. Modular invariance introduces constraints on the chiral asymmetry which can be satisfied for all models in the discrete series.     

Algebraic structure of topological superconformal field theory on Riemann surfaces

The algebraic structure of a topological superconformal field theory on a compact Riemann surface is investigated. The Krichever-Novikov [K-N] global operator formalism is used to obtain anN=4 super K-N algebra on a Riemann surface. Subsequently thisN=4 algebra is shown to posses anN=3 K-N subalgebra. TheN=3 subalgebra is then twisted to derive a topological version of the Krichever-Novikov algebra with a residualN=2 superconformal structure. The BRST charge of the associated topological field theory on the Riemann surface is shown to be genus dependent in this formalism and the global generalization of the BRST derivative conditions are obtained. The complete BRST structure of the theory is explicitly elucidated.     

Operator product expansion coefficients in N = 1 superconformal theory and slightly relevant perturbation

We have computed general four-point functions and obtained the operator-product-expansion coefficients in the discrete N = 1 superconformal theories using the method developed by Dotsenko and Fateev. As an application of our results, we have considered the effect of applying the slightly relevant perturbation on superconformal theories. For large m it is shown that the central charge c(m) shifts twice the minimal possible amount as c(m) → c(m − 2), in accordance with what the Witten index tr(−1)^F suggests.     

Renormalization theory in superspace

The auxiliary mass BPHZ renormalization procedure is extended to include theories defined in superspace. Ultraviolet and infrared power counting formulas for Feynman integrands in superspace are derived. A general momentum-superspace subtraction scheme is given which allows time-ordered Green functions of superfields to be defined as tempered distributions. Superfield normal product Green functions are introduced and the Zimmermann identity relating differently subtracted such products is established. Finally normal product field equations and the renormalized quantum action principle in superspace are derived.     

A grand superspace for unified field theories

Agrand superspace is proposed as the phase space for gauge field theories with a fixed structure groupG over a fixed space-time manifoldM. This superspace incorporatesall principal fiber bundles with these data. This phase space is the space of isomorphism classes ofall connections onall G-principal fiber bundles overM (fixedG andM). The justification for choosing this grand superspace for the phase space is that the space-time and the structure group are determinants of the physical theory, but the principal fiber bundle with the givenG andM is not. Grand superspace is studied in terms of a natural universal principal fiber bundle overM, canonically associated withM alone, and with a natural universal connection on this bundle. This bundle and its connection are universal in the sense that all connections on allG-principal fiber bundles (anyG) overM can be recovered from this universal bundle and its universal connection by a canonical construction. WhenG is Abelian, grand superspace is shown to be an Abelian group. Various subspaces of grand superspace consisting of the isomorphism classes of flat connections and of Yang-Mills connections are also discussed.     

Lattice models in statistical mechanics for N = 2 superconformal field theory

We study exactly solvable cyclic solid-on-solid models extended to arbitrary higher degrees of the fusion construction. A detailed calculation of their local state probabilities via the corner transfer matrix method is presented. The order parameters thus obtained include new characters of the conformal field theories. We discuss a series of lattice analogues of the N = 2 superconformal minimal models included in this family of the cyclic solid-on-solid models.     

Nonlocal current algebra and N = 2 superconformal field theory in two dimensions

We present a new construction of the unitary highest weight representations of the N = 2 superconformal algebras in two dimensions. This construction is based on the non-local current in the Z_N conformal theory and a free scalar field. It provides a physical realization of all the unitary N = 2 superconformal field theories by critical systems. The correlation functions of the theories can be calculated through this construction.     

Quantum deformedsu(m/n) algebra and superconformal algebra on quantum superspace

We study a deformedsu(m/n) algebra on a quantum superspace. Some interesting aspects of the deformed algebra are shown. As an application of the deformed algebra we construct a deformed superconformal algebra. From the deformedsu(1/4) algebra, we derive deformed Lorentz, translation of Minkowski space,iso(2, 2) and its supersymmetric algebras as closed subalgebras with consistent automorphisms.     

Taxonomy of heterotic superconformal field theories

We derive the massless spectrum of all heterotic two-dimensional superconformal field theories constructed by tensoring models from the discrete series (c<3) using diagonal and exceptional affine invariants (but not including the quotients by discrete groups). A comparison is made between these models and known manifold constructions lending some support to the conjecture that some of these are sigma models with Calabi-Yau target spaces.     

On the renormalization of topological Yang-Mills field theory in N = 1 superspace

We discuss the renormalization aspects of topological super-Yang-Mills field theory in N = 1 superspace. Our approach makes use of the regularization-independent BRS algebraic technique adapted to the case of an N = 1 supersymmetric model. We give the expression of the most general local counterterm to the classical action to all orders of the perturbative expansion. The counterterm is shown to be a BRS coboundary, implying that the cohomological properties of the supertopological theory are not affected by quantum effects. We also demonstrate the vanishing of the Callan-Symanzik β-function of the model by employing a recently discovered supersymmetric antighost Ward identity.     

A Clifford analysis approach to superspace

A new framework for studying superspace is given, based on methods from Clifford analysis. This leads to the introduction of both orthogonal and symplectic Clifford algebra generators, allowing for an easy and canonical introduction of a super-Dirac operator, a super-Laplace operator and the like. This framework is then used to define a super-Hodge coderivative, which, together with the exterior derivative, factorizes the Laplace operator. Finally both the cohomology of the exterior derivative and the homology of the Hodge operator on the level of polynomial-valued super-differential forms are studied. This leads to some interesting graphical representations and provides a better insight in the definition of the Berezin-integral.     

Simple superconformal field theories in two dimensions

Superconformal field theories with first-order lagrangians, the super BC-systems, are considered on an arbitrary Riemann surface with an arbitrary gravitino field. The corresponding functional integrals are carefully defined, and the Weyl, supersymmetry, and holomorphic anomalies are computed. All the anomalies have a common coefficient. The holomorphic anomaly involves terms quadratic in the gravitino field.