The cyclic and epicyclic sites

  title={The cyclic and epicyclic sites},
  author={Alain Connes and Caterina Consani},
  journal={Rendiconti del Seminario Matematico della Universit{\`a} di Padova},
  • A. Connes, C. Consani
  • Published 15 July 2014
  • Mathematics
  • 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… 
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