36 entangled officers of Euler

Il giorno 10 febbraio 2023 il Prof. Karol Życzkowski, Institute of Theoretical Physics, Jagiellonian University, Kraków, Poland, terrà il seguente seminario Title: "36 entangled officers of Euler: A quantum solution to a classically impossible problem"   Abstract:  A quantum combinatorial designs is composed of quantum states, arranged with a certain symmetry and balance. They determine distinguished quantum measurements and can be applied for quantum information processing. The negative solution to the famous problem of 36 officers of Euler implies that there are no two orthogonal Latin squares of order six.  We show that the problem has a solution, provided the officers are entangled, and construct orthogonal quantum Latin squares of this size. The solution can be visualized on a chessboard of size six, which shows that 36 officers are splitted in nine groups, each containing four entangled states. It allows us to construct a pure nonadditive quhex quantum error detection code.     https://physics.aps.org/articles/v15/29