ICTS

String theory has been a powerful enterprise in theoretical physics, which, apart from proposing a theory of everything, provides us a handful of dualities. One of the most surprising of them is the Gauge-String duality. But questions remain unanswered on the underlying mechanism and generality (e.g applicability to non-supersymmetric gauge theory) of this correspondence. 
In the first part of my talk, I will take some initial steps towards these aspects, in particular, I will demonstrate an explicit realization of the underlying mechanism of gauge-string duality for tensionless limit of $AdS_3/CFT_2$ and (a particular sector of) $AdS_5/CFT_4$ correspondence. I will then move on to put forward a string theory dual to large N (non-supersymmetric) pure two-dimensional Yang Mills theory. 
In the second part, I will probe into independent questions of consistency of string theory itself. In particular, I will comment on the positivity of the coefficients of string amplitudes when expanded into the partial waves at the massive poles in $D=4$. This positivity is demanded by unitarity. I will comment on the similar positivity of the Coon amplitude in $D=4$, the latter being an amplitude interpolating between a string amplitude and a scalar particle amplitude. 

Zoom link: https://icts-res-in.zoom.us/j/82181455971?pwd=YkFXenBGbFliZHY4eUY0Z3ZFRWw1UT09
Meeting ID: 821 8145 5971
Passcode: 346289