On the hyperreal dual Steenrod algebra

Michael A. Hill; Michael J. Hopkins

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arXiv · 2602.11010

On the hyperreal dual Steenrod algebra

Michael A. Hill·Michael J. Hopkins

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Abstract

We compute the dual Steenrod algebra for Bredon homology with constant coefficients $\underline{\mathbb Z}$ and $\underline{\mathbb Z}/2$ in the category of modules over $MU^{((G))}$, the norm to $G=C_{2^n}$ of $MU_{\mathbb R}$. Using this and an equivariant version of the Greenlees--Serre spectral sequence, we give a spectral sequence computing the $RO$-graded homotopy of the Eilenberg--Mac Lane spectrum $H\underline{\mathbb F}_2\otimes H\underline{\mathbb Z}$.

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Michael A. Hill, Michael J. Hopkins. 2026-02-11. On the hyperreal dual Steenrod algebra. https://arxiv.org/abs/2602.11010

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