相关论文: Non-minimal fields of the pure spinor string in ge…

In the framework of the pure spinor approach of superstring theories, we describe the Y-formalism and use it to compute the picture raised b-field. At the end we discuss briefly the new, non-minimal formalism of Berkovits and the related…

In this paper we begin the study of compactifications of the pure spinor formalism for superstrings. As a first example of such a process we study the case of the heterotic string in a Calabi-Yau background. We explicitly construct a BRST…

For the closed superstring, spin fields and bi-spinor states are defined directly in four spacetime dimensions. Explicit operator product expansions are given, including those for the internal superconformal field theory, which are…

We describe a pure spinor BRST cohomology framework to compactly represent ten-dimensional one-loop amplitudes involving any number of massless open- and closed-string states. The method of previous work to construct scalar and vectorial…

String field theory for the non-critical NSR string is described. In particular it gives string field theory for the 2D super-gravity coupled to a $\hat{c}=1$ matter field. For this purpose double-step pictures changing operators for the…

The linear theory of massive spin-two field in arbitrary curved background is investigated. In flat spacetime, the Fierz-Pauli model is well-known as the unique linear theory describing the massive spin-two field. On the other hand, in…

We show that there is (p-1)(p'-1) dimensional semi-relative BRST cohomology at each non-positive ghost number in the (p,p') minimal conformal field theory coupled to two dimensional quantum gravity. These closed string states are related to…

In this thesis we investigate the microphysics of cosmic strings in non-minimal quantum field theories. In particular we consider theories in which fermion fields couple to the strings, and those with larger symmetry groups, such as grand…

We study gauge theories of background fields associated to BRST quantized spinning particle models and identify background-independent algebraic structures which allow to systematically reduce the spectrum of fields and subject some of them…

The problem of the electromagnetic coupling for spin 3/2 fields is discussed. Following supergravity and some recent works in the field of classical supersymmetric particles, we find that the electromagnetic coupling must not obey a minimal…

The ghost for world-sheet reparametrization invariance is not a fundamental field in the pure spinor formalism. It is written as a combination of pure spinor variables which have conformal dimension two and such that it commutes with the…

In this article, we propose a new way to handle interactions between two scalar fields in the cosmological backdrop where one scalar field oscillates rapidly in the cosmological time scale while the other does not show any periodic behavior…

In this work we investigate the classical constraints imposed on the supergravity and super Yang-Mills backgrounds in the $\alpha'\to 0$ limit of the heterotic string using the pure spinor formalism. Guided by the recently observed…

The pure spinor heterotic string in a generic super Yang-Mills and supergravity background is considered. We determine the one-loop BRST anomaly at the cohomological level. We prove that it can be absorbed by consistent corrections of the…

We construct a covariant quantum superstring, extending Berkovits' approach by introducing new ghosts to relax the pure spinor constraints. The central charge of the underlying Kac-Moody algebra, which would lead to an anomaly in the BRST…

We complete the construction of vacuum string field theory by proposing a canonical choice of ghost kinetic term -- a local insertion of the ghost field at the string midpoint with an infinite normalization. This choice, supported by level…

We study the propagation of a probe massless nonminimally coupled scalar field in a fixed gravitational background of a cloud of strings in (2+1) dimensions. We obtain exact analytical expressions for the reflection coefficient, the…

We consider a recently proposed non-minimal matter coupling in massive gravity and multi-gravity. We argue that, when formulated in terms of unconstrained vielbeins, this matter coupling contains the primary constraints necessary to remove…

We construct analytic solutions in cubic open superstring field theory at higher superconformal ghost numbers.The solutions are the pure ghost ones and are given by combinations of Bell polynomials of bosonized superconformal ghost fields…

In the pure spinor formalism for the superstring, the b-ghost is a composite operator satisfying {Q,b}=T where Q is the pure spinor BRST operator and T is the holomorphic stress tensor. The b-ghost is holomorphic in a flat target-space…