K-theory and elliptic operators
  This expository paper is an introductory text on topological K-theory and the Atiyah-Singer index theorem, suitable for graduate students or advanced undegraduates already possessing a background in algebraic topology. The bulk of the material presented here is distilled from Atiyah's classic "K-Theory" text, as well as his series of seminal papers "The Index of Elliptic Operators" with Singer. Additional topics include equivariant K-theory, the G-index theorem, and Bott's paper "The Index Theorem for Homogeneous Differential Operators". It also includes an appendix with a proof of Bott periodicity, as well as sketches of proofs for both the standard and equivariant versions of the K-theory Thom isomorphism theorem, in terms of the index for families of elliptic operators. A second appendix derives the Atiyah-Hirzebruch spectral sequence. This text originated as notes from a series of lectures given by the author as an undergraduate at Princeton. In its current form, the author has used it for graduate courses at the University of Oregon. 
Gregory D. Landweber (University of Oregon)