Xue-Xiang Xu

Information Geometry of Four-Parameter Single-Qutrit States: From Quantum to Semiclassical Geometric Tensors

The gap between the classical and quantum Fisher information matrices (CFIM and QFIM) separates what is operationally accessible through measurements from what is intrinsic to a quantum state. In the multiparameter setting, this quantum obstruction is generically not saturable. Motivated by the recently introduced semi...