High Energy Theory Seminar

I will discuss new universal bounds on the spectra of two-dimensional unitary, compact conformal field theories coming from the modular bootstrap. In the presence of a twist gap amongst the Virasoro primary operators (where twist is defined as the difference between total conformal dimension and spin), I will show that there is a universal expression for the density of states that extends beyond the usual Cardy regime. I will also describe a new upper bound on the lowest twist primary operator present in any CFT. For theories holographically dual to large-radius gravity in $AdS_3$, this new bound is below the BTZ threshold, which implies that states that cannot be described as BTZ black holes must exist.