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Title: A NEW PERSPECTIVE ON SEMI-RETRACTIONS AND THE RAMSEY PROPERTY
Abstract We investigate the notion of a semi-retraction between two first-order structures (in typically different signatures) that was introduced by the second author as a link between the Ramsey property and generalized indiscernible sequences. We look at semi-retractions through a new lens establishing transfers of the Ramsey property and finite Ramsey degrees under quite general conditions that are optimal as demonstrated by counterexamples. Finally, we compare semi-retractions to the category theoretic notion of a pre-adjunction.  more » « less
Award ID(s):
2246995 1953955
PAR ID:
10506443
Author(s) / Creator(s):
;
Publisher / Repository:
Cambridge University Press
Date Published:
Journal Name:
The Journal of Symbolic Logic
ISSN:
0022-4812
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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