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arXiv · 1511.03001

New-from-old full dualities via axiomatisation

Brian A. Davey·Jane G. Pitkethly·Ross Willard
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Abstract

We clarify what it means for two full dualities based on the same algebra to be different. Our main theorem gives conditions on two different alter egos of a finite algebra under which, if one yields a full duality, then the other does too. We use this theorem to obtain a better understanding of several important examples from the theory of natural dualities. Throughout the paper, a fundamental role is played by the universal Horn theory of the dual classes.

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Brian A. Davey, Jane G. Pitkethly, Ross Willard. 2018-01-30. New-from-old full dualities via axiomatisation. https://arxiv.org/abs/1511.03001

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