Michele Arzano

Hopf-algebra deformations of spacetime symmetries, as they arise in models of non-commutative spacetimes, modify the very notion of how symmetries act on composite systems. I will discuss two complementary aspects of this structure, focusing on its implications for quantum dynamics and quantum information. In the first part, I show that deformed coproducts generically induce operator entanglement at the algebraic level. Using the quantum group U_q(su(2)) as a minimal and exactly solvable example, I demonstrate how a deformation that is invisible at the single-qubit level appears in the two-qubit sector through the non-cocommutativity of the coproduct. The resulting composite generators define intrinsically nonlocal unitaries whose entangling power can be computed in closed form and traced directly to their operator entanglement. This provides a concrete mechanism by which non-commutative symmetries enforce a baseline of entanglement independently of dynamics or interactions. In the second part, I critically examine claims that similar Hopf-algebra deformations of time-translation generators may lead to an intrinsic form of decoherence described by Lindblad-type evolution. By analyzing the definition of time evolution via generalized adjoint actions, I show that a consistent and physically viable formulation always leads to unitary von Neumann dynamics.