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arXiv · 1701.02020

Linear orders: when embeddability and epimorphism agree

Riccardo Camerlo·Raphaël Carroy·Alberto Marcone
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Abstract

When a linear order has an order preserving surjection onto each of its suborders we say that it is strongly surjective. We prove that the set of countable strongly surjective linear orders is complete for the class of sets which are the union of an analytic and a coanalytic set. Using hypotheses beyond ZFC, we prove the existence of uncountable strongly surjective orders.

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Riccardo Camerlo, Raphaël Carroy, Alberto Marcone. 2017-01-08. Linear orders: when embeddability and epimorphism agree. https://doi.org/10.1142/s021906131950003x

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