Dirac Operators and Domain Walls

Dirac Operators

Dirac Operators and Boundaries

Notes from my lectures in Fall 2003 in MIT course 18.158.

Dirac Operators and Spectral Geometry

Collapsing and Dirac-type Operators

We analyze the limit of the spectrum of a geometric Dirac-type operator under a collapse with bounded diameter and bounded sectional curvature. In the case of a smooth limit space B, we show that the limit of the spectrum is given by the spectrum of a certain first-order differential operator on B, which can be constructed using superconnections. In the case of a general limit space X , we expr...

Fourier Multipliers and Dirac Operators

We use Fourier multipliers of the Dirac operator and Cauchy transform to obtain composition theorems and integral representations. In particular we calculate the multiplier of the Π-operator. This operator is the hypercomplex version of the Beurling Ahlfors transform in the plane. The hypercomplex Beuling Ahlfors transform is a direct generalization of the Beurling Ahlfors transform and reduces...