ON QUANTUM BRST COHOMOLOGY

2009 ◽  
Vol 06 (07) ◽  
pp. 1151-1160
Author(s):  
Z. BENTALHA ◽  
M. TAHIRI
Keyword(s):  
Brst Operator ◽  
Brst Cohomology

Within bicovariant differential calculi framework, the BRST operator Ω is constructed. We showed that Ω is nil-potent (Ω2=0).

scholarly journals sℓ(2)−4 WZW MODEL AS AN (N=4)-SUPERSYMMETRIC BOSONIC STRING WITH c=−2 MATTER

1996 ◽  
Vol 11 (15) ◽  
pp. 2721-2748 ◽  
Author(s):  
A.M. SEMIKHATOV ◽  
I. YU. TIPUNIN
Keyword(s):  
Spectral Sequence ◽  
Current Algebra ◽  
Bosonic String ◽  
Singular Vectors ◽  
Brst Operator ◽  
Irreducible Modules ◽  
Brst Cohomology ◽  
Operator Construction

We consider the sℓ(2) current algebra at level k=−4 when the sℓ(2) BRST operator is nilpotent. We formulate a spectral sequence converging to the cohomology of this BRST operator. At the second term in the spectral sequence, we observe the existence of an N=4 algebra. This algebra is generated in a c=−2 bosonic string whose BRST operator [Formula: see text] represents the next term in the spectral sequence. We realize the cohomology of the irreducible modules as [Formula: see text] primitives of theN=4 singular vectors and relate the latter to the Lian–Zuckerman states of c=−2 matter. The relation between the sℓ(2)−4 WZW model and the c=−2 bosonic string is established both at the level of BRST cohomology and at the level of an explicit operator construction. The relation of the N=4 algebra to the known symmetries of matter+gravity systems is also investigated.

GENERALIZED CONNECTION FORMALISM AND BRST COHOMOLOGY STRUCTURE FOR BF THEORIES

1998 ◽  
Vol 13 (23) ◽  
pp. 1837-1844 ◽  
Author(s):  
A. ABDESSELAM ◽  
M. TAHIRI
Keyword(s):  
Brst Symmetry ◽  
Brst Operator ◽  
Exact Quantum ◽  
Brst Cohomology ◽  
Quantum Action ◽  
Arbitrary Dimensions

The non-Abelian BF theories in arbitrary dimensions are studied in a generalized connection formalism. This gives rise to the off-shell nilpotent BRST operator which permits construction of BRST exact quantum action. A set of operators satisfying the descent equations is derived from the generalized curvature; but it cannot lead to non-trivial observables. An off-shell superalgebra of Wess–Zumino type, containing the vector supersymmetry and the BRST symmetry, is also derived.

scholarly journals (NON)TRIVIALITY OF PURE SPINORS AND EXACT PURE SPINOR–RNS MAP

2009 ◽  
Vol 24 (14) ◽  
pp. 2677-2687 ◽  
Author(s):  
DIMITRI POLYAKOV
Keyword(s):  
Hilbert Space ◽  
String Theory ◽  
Vertex Operator ◽  
Similarity Transformation ◽  
Pure Spinor ◽  
Brst Operator ◽  
Variable Λ ◽  
Brst Cohomology ◽  
Spinor Formalism ◽  
Pure Spinor Formalism

All the BRST-invariant operators in pure spinor formalism in d = 10 can be represented as BRST commutators, such as [Formula: see text] where λ+ is the U(5) component of the pure spinor transforming as [Formula: see text]. Therefore, in order to secure nontriviality of BRST cohomology in pure spinor string theory, one has to introduce "small Hilbert space" and "small operator algebra" for pure spinors, analogous to those existing in RNS formalism. As any invariant vertex operator in RNS string theory can also represented as a commutator V = {Q brst , LV} where L = -4c∂ξξe-2ϕ, we show that mapping [Formula: see text] to L leads to identification of the pure spinor variable λα in terms of RNS variables without any additional nonminimal fields. We construct the RNS operator satisfying all the properties of λα and show that the pure spinor BRST operator ∮λαdα is mapped (up to similarity transformation) to the BRST operator of RNS theory under such a construction.

TOPOLOGICAL CONFORMAL ALGEBRA IN POLYAKOV’S LIGHT-CONE GAUGE GRAVITY

1992 ◽  
Vol 07 (35) ◽  
pp. 3291-3302 ◽  
Author(s):  
KIYONORI YAMADA
Keyword(s):  
Light Cone ◽  
Matter Field ◽  
Conformal Algebra ◽  
Two Dimensional ◽  
Topological Algebras ◽  
Light Cone Gauge ◽  
Brst Cohomology ◽  
Dimensional Gravity ◽  
Conformal Gauge ◽  
Gauge Gravity

We show that the two-dimensional gravity coupled to c=−2 matter field in Polyakov’s light-cone gauge has a twisted N=2 superconformal algebra. We also show that the BRST cohomology in the light-cone gauge actually coincides with that in the conformal gauge. Based on this observation the relations between the topological algebras are discussed.

scholarly journals BRST operator for superconformal algebras with quadratic nonlinearity

1994 ◽  
Vol 326 (3-4) ◽  
pp. 243-250 ◽  
Author(s):  
Z. Khviengia ◽  
E. Sezgin
Keyword(s):  
Quadratic Nonlinearity ◽  
Brst Operator

scholarly journals HAMILTONIAN COHOMOLOGICAL DERIVATION OF FOUR-DIMENSIONAL NONLINEAR GAUGE THEORIES

2002 ◽  
Vol 17 (16) ◽  
pp. 2191-2210 ◽  
Author(s):  
C. BIZDADEA ◽  
E. M. CIOROIANU ◽  
S. O. SALIU
Keyword(s):  
Gauge Theory ◽  
Gauge Theories ◽  
Scalar Fields ◽  
Gauge Algebra ◽  
Brst Cohomology ◽  
Nonlinear Gauge

Consistent couplings among a set of scalar fields, two types of one-forms and a system of two-forms are investigated in the light of the Hamiltonian BRST cohomology, giving a four-dimensional nonlinear gauge theory. The emerging interactions deform the first-class constraints, the Hamiltonian gauge algebra, as well as the reducibility relations.

scholarly journals On the BRST operator structure of the N = 2 string

1993 ◽  
Vol 400 (1-3) ◽  
pp. 145-160 ◽  
Author(s):  
Amit Giveon ◽  
Martin Roček
Keyword(s):  
Brst Operator ◽  
Operator Structure

ONE-LOOP VACUUM ENERGY AT THE TACHYON VACUUM

2013 ◽  
Vol 21 ◽  
pp. 157-158
Author(s):  
SHOKO INATOMI
Keyword(s):  
Field Theory ◽  
Quantum Theory ◽  
String Field Theory ◽  
Vacuum Energy ◽  
Open String ◽  
Brst Operator ◽  
Identity Based ◽  
Homotopy Operators

We consider one-loop vacuum energy at the tachyon vacuum in cubic bosonic open string field theory. The BRST operator Ql in the theory around an identity-based solution is believed to represent a kinetic operator at the tachyon vacuum. Using homotopy operators for Ql, we find that one-loop vacuum energy at the tachyon vacuum is independent of moduli such as interbrane distances. This result can be interpreted as support for the annihilation of D-branes at the tachyon vacuum even in the quantum theory.

Sign in / Sign up

Export Citation Format

Share Document