3 papers
math-ph2024
On the rational invariants of quantum systems of -qubits
Luca Candelori, Vladimir Y. Chernyak, John R. Klein
For an -qubit system, a rational function on the space of mixed states which is invariant with respect to the action of the group of local symmetries may be viewed as a detailed…
math-ph2024
On the variety of X-states
Luca Candelori, Vladimir Y. Chernyak, John R. Klein
We introduce the notion of an X-state on -qubits. After taking the Zariski closure of the set of X-states in the space of all mixed states, we obtain a complex algebraic variety…
quant-ph2023
Effective Rationality for Local Unitary Invariants of Mixed States of Two Qubits
Luca Candelori, Vladimir Y. Chernyak, John R. Klein +1
We calculate the field of rational local unitary invariants for mixed states of two qubits, by employing methods from algebraic geometry. We prove that this field is rational (i.e.…