Field theory actions for ambitwistor string and superstring

Abstract

We analyze the free ambitwistor string field theory action for the bosonic string, heterotic string and both GSO sectors of the Type II string. The spectrum contains nonunitary states and provides an interesting consistency test for one-loop ambitwistor string computations.

Bosonic sectorized strings and the (DF)2 theory

“…(1) which, in the tensionless limit, has the same form as the one found in [15]. Of course, this had to be the case since the vertex operator (2.29) preserves its form as T → 0, while the BRST operator reduces to the (bosonic) ambitwistor one, as is evident from (2.15).…”

“…Note that the complete energy-momentum tensor is given by 12) and it is BRST exact, since {Q, while the BRST charge is rewritten as 15) and the familiar Virasoro structure emerges. The tensionless limit of Q is now very clear: it is precisely the BRST operator introduced by Mason and Skinner for the bosonic ambitwistor string [3].…”

“…Here the notation for the fields was chosen so as to agree with the ambitwistor construction of [15], where it was demonstrated that the free field dynamics associated to the fields above involve higher derivative operators. This result follows naturally from our construction above.…”

“…Inspired by Zwiebach's closed string action [16], the kinetic action for ambitwistor strings was built in [15]. We will use the same prescription for the tensionful model and the kinetic action will be defined by…”

“…As in the heterotic case, the two sectors emulate the left-and right-moving sectors of the usual string theory, but all worldsheet fields are holomorphic. Using methods similar to the ones used in [15] for the ambitwistor string -which in turn were based on [16] -, we compute its physical spectrum and the correspondent kinetic action. We also analyze the 3-point tree level functions.…”