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Andrew Stacey
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References for equivariant K-theory

I want a good introduction to localization in equivariant $K$-theory. This introduction can be simple in several ways:

  1. I only care about torus actions.
  2. I only care about $K^0$.
  3. I only care about very nice spaces. I would be fine if the only spaces considered were $G/P$'s and smooth projective toric varieties.

However, I want this exposition to include the following:

  1. How to compute a $K$-class from a Hilbert series.
  2. Given $X \to Y$ nice spaces, how describe push back and pull forward in terms of the map $X^T \to Y^T$.
  3. Ideally, this reference would also give the generators and relations presentation of $K$-theory for the sort of examples mentioned above. I mean formulas like $$K^0(\mathbb{P}^{n-1}) = K^0(\mathrm{pt})[t, t^{-1}]/(t-\chi\_1)(t-\chi\_2) ... (t - \chi_n)$$ where $\chi_i$ are the characters of the torus action. But I can find other references for this sort of thing.

The best reference I currently know is the appendix to Knutson-Rosu.

David E Speyer
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