Communications in Number Theory and Physics
Volume 2 (2008)
Extremal $\CN=(2,2)$ 2D conformal field theories and constraints of modularity
Pages: 743 – 801
We explore the constraints on the spectrum of primaryfields\break implied by modularity of the elliptic genusof $\CN=(2,2)$ 2D CFTs. We show that such constraints havenontrivial implications for the existence of “extremal”$\CN=(2,2)$ conformal field theories. Applications toAdS$_3$ supergravity and flux compactifications areaddressed.