24 research outputs found
A Note on T-dualities in the Pure Spinor Heterotic String
In this note we study the preservation of the classical pure spinor BRST constraints under super T-duality transformations. We also determine the invariance of the one-loop conformal invariance and of the local gauge and Lorentz anomalies under the super Tdualities
BRST Anomaly and Superspace Constraints of the Pure Spinor Heterotic String in a Curved Background
The pure spinor heterotic string in a generic super Yang-Mills and supergravity background is onsidered. We determine the one-loop BRST anomaly at the cohomological level. We prove that it can be absorbed by consistent corrections of the classical constraints due to Berkovits and Howe, in agreement with the Green-Schwarz cancelation mechanism
A Note on T-dualities in the Pure Spinor Heterotic String
In this note we study the preservation of the classical pure spinor BRST
constraints under super T-duality transformations. We also determine the
invariance of the one-loop conformal invariance and of the local gauge and
Lorentz anomalies under the super T-dualities.Comment: References adde
A Note on the Classical BRST Symmetry of the Pure Spinor String in a Curved Background
The classical pure spinor version of the heterotic superstring in a
supergravity and super Yang-Mills background is considered. We obtain the BRST
transformations of the world-sheet fields. They are consistent with the
constraints obtained from the nilpotence of the BSRT charge and the
holomorphicity of the BRST current.Comment: References adde
Reply to the comment by D. Kreimer and E. Mielke
We respond to the comment by Kreimer et. al. about the torsional contribution
to the chiral anomaly in curved spacetimes. We discuss their claims and refute
its main conclusion.Comment: 9 pages, revte
BRST Anomaly and Superspace Constraints of the Pure Spinor Heterotic String in a Curved Background
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 classical constraints due to Berkovits and Howe, in
agreement with the Green-Schwarz cancelation mechanism.Comment: harvmac-big, 18 pages; references added; minor correction
Massive Superstring Vertex Operator in D=10 Superspace
Using the pure spinor formalism for the superstring, the vertex operator for
the first massive states of the open superstring is constructed in a manifestly
super-Poincar\'e covariant manner. This vertex operator describes a massive
spin-two multiplet in terms of ten-dimensional superfields.Comment: Added reference
Superstring Vertex Operators in an AdS_5 x S^5 Background
A quantizable action has recently been proposed for the superstring in an
AdS_5 x S^5 background with Ramond-Ramond flux. In this paper, we construct
physical vertex operators corresponding to on-shell fluctuations around the
AdS_5 x S^5 background. The structure of these AdS_5 x S^5 vertex operators
closely resembles the structure of the massless vertex operators in a flat
background.Comment: 13 pages harvmac (large
Topological Invariants, Instantons and Chiral Anomaly on Spaces with Torsion
In a spacetime with nonvanishing torsion there can occur topologically stable
configurations associated with the frame bundle which are independent of the
curvature. The relevant topological invariants are integrals of local scalar
densities first discussed by Nieh and Yan (N-Y). In four dimensions, the N-Y
form is the only closed
4-form invariant under local Lorentz rotations associated with the torsion of
the manifold. The integral of over a compact D-dimensional (Euclidean)
manifold is shown to be a topological invariant related to the Pontryagin
classes of SO(D+1) and SO(D). An explicit example of a topologically nontrivial
configuration carrying nonvanishing instanton number proportional to
is costructed. The chiral anomaly in a four-dimensional spacetime with torsion
is also shown to contain a contribution proportional to , besides the usual
Pontryagin density related to the spacetime curvature. The violation of chiral
symmetry can thus depend on the instanton number of the tangent frame bundle of
the manifold. Similar invariants can be constructed in D>4 dimensions and the
existence of the corresponding nontrivial excitations is also discussed.Comment: 6 pages, RevTeX, no figures, two column
4-point effective actions in open and closed superstring theory
Recently the effective action for the 4-point functions in abelian open
superstring theory has been derived, giving an explicit construction of the
bosonic and fermionic terms of this infinite series. In the present
work we generalize this result to the nonabelian case. We test our result, at
and order, with several existing versions for these
terms, finding agreement in most of the cases. We also apply these ideas to
derive the effective action for the 4-point functions of the NS-NS sector of
closed superstring theory, to all order in .Comment: 26 pages, 1 figure. To appear in JHE