Topics in Open Topological Strings

TL;DR

This thesis explores key aspects of open topological string theory, including tadpole cancellation, open-closed effective field theories, and dualities, providing new insights and extending previous analyses from target space and worldsheet perspectives.

Contribution

It introduces new results on open-closed duality and extends the analysis of effective field theories in open topological strings, building upon and expanding prior work.

Findings

Demonstrated the necessity of tadpole cancellation for moduli decoupling

Derived known and new tree-level amplitudes in target space

Extended open-closed duality analysis from worldsheet and target space viewpoints

Abstract

This thesis is based on some selected topics in open topological string theory which I have worked on during my Ph.D. It comprises an introductory part where I have focused on the points most needed for the later chapters, trading completeness for conciseness and clarity. Then, following [12], we discuss tadpole cancellation for topological strings where we mainly show how its implementation is needed for ensuring the same "odd" moduli decoupling encountered in the closed theory. Next we move to analyse how the open and closed effective field theories for the B model interact writing the complete Lagrangian. We first check it deriving some already known tree level amplitudes in term of target space quantities, and then we extend the recipe to new results; later we implement open closed duality from a target field theory perspective. This last subject is also analysed from a worldsheet point of view extending the analysis of [13]. Some ideas for future research are briefly reported.