Comments on T-dualities of Ramond-Ramond Potentials

Fukuma, Masafumi; Oota, Takeshi; Tanaka, Hirokazu

Comments on T-dualities of Ramond-Ramond Potentials

Authors

Fukuma, Masafumi

Oota, Takeshi

Tanaka, Hirokazu

Description

The type IIA/IIB effective actions compactified on T^d are known to be invariant under the T-duality group SO(d, d; Z) although the invariance of the R-R sector is not so direct to see. Inspired by a work of Brace, Morariu and Zumino,we introduce new potentials which are mixture of R-R potentials and the NS-NS 2-form in order to make the invariant structure of R-R sector more transparent. We give a simple proof that if these new potentials transform as a Majorana-Weyl spinor of SO(d, d; Z), the effective actions are indeed invariant under the T-duality group. The argument is made in such a way that it can apply to Kaluza-Klein forms of arbitrary degree. We also demonstrate that these new fields simplify all the expressions including the Chern-Simons term.
26 pages; LaTeX; major version up; discussion on the Chern-Simons term added; references added