A categorical description of simple Beth companions

Luca Carai, Miriam Kurtzhals, Tommaso Moraschini

A pp expansion of a quasivariety $\mathsf{K}$ is said to be simple when it is of the form $\mathsf{K}[{\mathcal{L}}_{\mathcal{F}}]$. For instance, when $\mathsf{K}$ has the amalgamatio…