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arXiv · 1310.5076

There is no finite-variable equational axiomatization of representable relation algebras over weakly representable relation algebras

Jeremy F. Alm·Robin Hirsch·Roger D. Maddux
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Abstract

We prove that any equational basis that defines RRA over wRRA must contain infinitely many variables. The proof uses a construction of arbitrarily large finite weakly representable but not representable relation algebras whose "small" subalgebras are representable.

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Jeremy F. Alm, Robin Hirsch, Roger D. Maddux. 2016-07-07. There is no finite-variable equational axiomatization of representable relation algebras over weakly representable relation algebras. https://doi.org/10.1017/s1755020316000265

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