Contents

PACS Classification: 02.40.Ky, 03.50.Kk, 03.65.Sq, 11.30.Pb, 12.60.Jv MSC Classification: 58A50, 14H55, 32G15

1. Introduction

3. Torsion on Riemann surfaces

4. The Dirac action on Riemannian surfaces and supersymmetry