Half-string oscillator approach to string field theory (ghost sector II)

130

254

In previous papers we built (multiple) D-branes in flat space-time as classical solutions of the string field theory based on the tachyon vacuum. In this paper we construct classical solutions describing all D-branes in any fixed space-time background defined by a two dimensional CFT of central charge 26. A key role is played by the geometrical definition of the sliver state in general boundary CFT's. The correct values for ratios of D-brane tensions arise because the norm of the sliver solution is naturally related to the disk partition function of the appropriate boundary CFT. We also explore the possibility of reproducing the known spectrum of physical states on a D-brane as deformations of the sliver.

Section: Factorization Ansatz For Gauge Transformationsmentioning

confidence: 99%

Boundary CFT construction of D-branes in vacuum string field theory

Rastelli

Sen

Zwiebach

2001

130

254

“…where we integrate over the half-string y. In [12], Z was absorbed in the integration measure 8 [dy], but here we want to define the measure in the obvious way: [dy] = dy n , as a product over all half-string mode measures. And similarly for the path integral over whole-string modes:…”

Section: The Overall Normalizationmentioning

confidence: 99%

Some exact results on the matter star-product in the half-string formalism

Moeller

2002

We show that the D25 sliver wavefunction, just as the D-instanton sliver, factorizes when expressed in terms of half-string coordinates. We also calculate analytically the star-product of two zero-momentum eigenstates ofx using the vertex in the oscillator basis, thereby showing that the star-product in the matter sector can indeed be seen as multiplication of matrices acting on the space of functionals of half strings. We then use the above results to establish that the matrices ρ 1,2 , conjectured by Rastelli, Sen and Zwiebach to be left and right projectors on the sliver, are indeed so.

“…We are attempting to confront these difficulties, starting with the very concrete problem of analytically verifying Sen's conjectures, with the hope of then generalizing the algebraic framework in a way that could be truly background independent. Other approaches to a halfstring operator formalism for open string field theory have appeared in [18,19,20,21,22,23].…”

Section: Introductionmentioning

confidence: 99%

Split string field theory II

Gross¹,

Taylor²

2001

105

We describe the ghost sector of cubic string field theory in terms of degrees of freedom on the two halves of a split string. In particular, we represent a class of pure ghost BRST operators as operators on the space of half-string functionals. These BRST operators were postulated by Rastelli, Sen, and Zwiebach to give a description of cubic string field theory in the closed string vacuum arising from condensation of a D25-brane in the original tachyonic theory. We find a class of solutions for the ghost equations of motion using the pure ghost BRST operators. We find a vanishing action for these solutions, and discuss possible interpretations of this result. The form of the solutions we find in the pure ghost theory suggests an analogous class of solutions in the original theory on the D25-brane with BRST operator Q B coupling the matter and ghost sectors.