Characterizing Jordan embeddings between block upper-triangular subalgebras via preserving properties

Ilja Gogić, Tatjana Petek, Mateo Tomašević

Let $M_n$ be the algebra of $n\times n$ complex matrices. We consider arbitrary subalgebras $\mathcal{A}$ of $M_n$ which contain the algebra of all upper-triangular matrices (i.e.…