@article{Connes2014TheCA,
title={The cyclic and epicyclic sites},
author={Alain Connes and Caterina Consani},
journal={Rendiconti del Seminario Matematico della Universit{\`a} di Padova},
year={2014},
volume={134},
pages={197-237}
}

Rendiconti del Seminario Matematico della Università di Padova

We determine the points of the epicyclic topos which plays a key role in the geometric encoding of cyclic homology and the lambda operations. We show that the category of points of the epicyclic topos is equivalent to projective geometry in characteristic one over algebraic extensions of the innite semield of \max-plus integers" Zmax. An object of this category is a pair (E;K) of a semimodule E over an algebraic extension K of Zmax. The morphisms are projective classes of semilinear maps… Expand

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Abstract We show that the cyclic and epicyclic categories which play a key role in the encoding of cyclic homology and the lambda operations, are obtained from projective geometry in characteristic… Expand

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