**Abstract: I** will start from the basis of T-duality in string theory, introduce how T-duality connects the different string theories and map them to M-theory. In the end I will talk about the T-duality in double field theory, especially how T-duality connects the geometric and non-geometric fluxes in double field theory. By introducing T-duality, I will try to give a general picture of string theory and double field theory which is also the topic of my doctoral project.

Nov 04, 2013 | 02:15 PM

SR 119, Arnimallee 3