# Real topological Hochschild homology via the norm and Real Witt vectors

@inproceedings{AngeliniKnoll2021RealTH, title={Real topological Hochschild homology via the norm and Real Witt vectors}, author={Gabe Angelini-Knoll and Teena Gerhardt and Michael A. Hill}, year={2021} }

We prove that Real topological Hochschild homology can be characterized as the norm from the cyclic group of order 2 to the orthogonal group O(2). From this perspective, we then prove a multiplicative double coset formula for the restriction of this norm to dihedral groups of order 2m. This informs our new definition of Real Hochschild homology of rings with anti-involution, which we show is the algebraic analogue of Real topological Hochschild homology. Using extra structure on Real Hochschild…

## One Citation

### Reflexive homology

- Mathematics
- 2022

. Reﬂexive homology is the homology theory associated to the reﬂexive crossed simplicial group; one of the fundamental crossed simplicial groups. It is the most general way to extend Hochschild…

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