collaborators

5 papers

math.OA2026

The reduced Hao-Ng isomorphism problem for non-degenerate product systems

Ioannis Apollon Paraskevas

We prove that the reduced Hao-Ng isomorphism problem has an affirmative answer for a generalised gauge action of a locally compact Hausdorff group on a non-degenerate product syste…

math.OA2026

Morita equivalence for quantum graphs

Alexandros Chatzinikolaou, Gage Hoefer, Nikolaos Koutsonikos-Kouloumpis +1

We introduce an operator-algebraic framework for Morita equivalence of quantum graphs based on -equivalence of operator systems introduced by Eleftherakis, Kakariadis and Todor…

math.OA2026

On the embeddings of selfadjoint operator spaces

Alexandros Chatzinikolaou, Evgenios T. A. Kakariadis, Se-Jin Kim +1

We investigate when a map on a selfadjoint operator space is an embedding, i.e., when its unitisation in the sense of Werner is completely isometric. Combining with results of…

math.OA2026

On hyperrigidity and non-degenerate C*-correspondences

Joseph A. Dessi, Evgenios T. A. Kakariadis, Ioannis Apollon Paraskevas

We revisit the results of Kim, and of Katsoulis and Ramsey concerning hyperrigidity for non-degenerate C*-correspondences. We show that the tensor algebra is hyperrigid, if and onl…

math.OA2025

On Fock covariance for product systems and the reduced Hao-Ng isomorphism problem by discrete actions

Evgenios T. A. Kakariadis, Ioannis Apollon Paraskevas

We provide a characterisation of equivariant Fock covariant injective representations for product systems. We show that this characterisation coincides with Nica covariance for com…