bundles

cohomology

# Contents

## Definition

A circle bundle is a principal bundle for the circle group $S^1$. Equivalently this is a $U(1)$-principal bundle, for the unitary group $U(1)$.

Under the canonical representation $\mathbf{B}U(1) \to Vect_{\mathbb{C}}$ the corresponding associated bundle is a complex line bundle.

## Examples

Revised on April 13, 2013 23:46:58 by Urs Schreiber (89.204.139.110)