Galois Theory and Lubin-tate Cochains on Classifying Spaces
نویسنده
چکیده
We consider brave new cochain extensions F (BG+, R) −→ F (EG+, R), where R is either a Lubin-Tate spectrum En or the related 2-periodic Morava K-theory Kn, and G is a finite group. When R is an Eilenberg-Mac Lane spectrum, in some good cases such an extension is a G-Galois extension in the sense of John Rognes, but not always faithful. We prove that for En and Kn these extensions are always faithful in the Kn local category. However, for a cyclic p-group Cpr , the cochain extension F (BCpr+, En) −→ F (ECpr+, En) is not a Galois extension because it ramifies. As a consequence, it follows that the En-theory Eilenberg-Moore spectral sequence for G and BG does not always converge to its expected target.
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