Chiral Algebras of (0,2) Models

Understand

We explore two-dimensional sigma models with (0,2) supersymmetry through their chiral algebras.

• Perturbatively, the chiral algebras of (0,2) models have a rich infinite-dimensional structure described by the cohomology of a sheaf of chiral differential operators.
• Nonperturbatively, instantons can deform this structure drastically.
• We show that under some conditions they even annihilate the whole algebra, thereby triggering the spontaneous breaking of supersymmetry.