String Theory Journal Club

In recent years there has been a surge of interest in the matrix models in the context of 2d gravity. These models reproduce, via topological recursion, n-point functions of (super)JT gravity to all orders in perturbation theory in $G_N$ and thus are hoped to be windows into non-perturbative quantum gravity. Nevertheless, finding these matrix models explicitly is not an easy task. The methods used so far are getting computationally more involved as one increases the number of supersymmetries. Moreover, their success depends on an infinite number of seemingly accidental cancellations. We propose a new scheme of mapping supergravities into matrix models that is much simpler and makes all these cancellations explicit. As a corollary, we show that the spectrum of such matrix models is very rigid. In particular, the BPS part of their spectrum is uniquely determined by the non-BPS part. Joint work with Clifford Johnson.