Fixed Points Theorems for Non-Transitive Relations

  title={Fixed Points Theorems for Non-Transitive Relations},
  author={J{\'e}r{\'e}my Dubut and Akihisa Yamada},
  journal={Log. Methods Comput. Sci.},
In this paper, we develop an Isabelle/HOL library of order-theoretic fixed-point theorems. We keep our formalization as general as possible: we reprove several well-known results about complete orders, often with only antisymmetry or attractivity, a mild condition implied by either antisymmetry or transitivity. In particular, we generalize various theorems ensuring the existence of a quasi-fixed point of monotone maps over complete relations, and show that the set of (quasi-)fixed points is… 

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