Minimal lambda-theories by ultraproducts

  title={Minimal lambda-theories by ultraproducts},
  author={Antonio Bucciarelli and Alberto Carraro and Antonino Salibra},
  booktitle={Workshop on Logical and Semantic Frameworks with Applications},
A longstanding open problem in lambda calculus is whether there exist continuous models of the untyped lambda calculus whose theory is exactly the least lambda-theory lb or the least sensible lambda-theory H (generated by equating all the unsolvable terms). A related question is whether, given a class of lambda models, there is a minimal lambda-theory represented by it. In this paper, we give a general tool to answer positively to this question and we apply it to a wide class of webbed models… 

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