Lecture 12 Mar

Based on material in Chapter 14 of Zwiebach, we wrapped up the story of the mass of fundamental open strings stretched between stacks of Dp and Dq branes (StringsBetweenDpAndDqBranes). We also gave a first introduction to T-duality (IntroducingTduality).

Before Friday’s class, please study Section 16.1-16.3 of Z-bach on the Hagedorn temperature. Most importantly, please study Chapter 17 of Z-bach on T-duality for both closed and open strings (TdualityOpenClosedStrings). This chapter in particular is important for cementing the notion of T-duality of closed strings in our brains (heheh, not branes…). T-duality is particularly important intellectually in a course about string theory, because it was the first duality symmetry to be well- understood.