qu an tph ] 1 1 O ct 2 01 0 Approximating incompatible von Neumann measurements simultaneously

Teiko Heinosaari, Maria Anastasia Jivulescu, 2 Daniel Reitzner, and Mario Ziman 4 Niels Bohr Institute, Blegdamsvej 17, 2100 Copenhagen, Denmark Department of Mathematics, University Politehnica Timisoara, P-ta Victoriei Nr. 2, 300006 Timisoara, Romania Institute of Physics, Slovak Academy of Sciences, Dúbravská cesta 9, 845 11 Bratislava, Slovakia Faculty of Informatics, Masaryk University, Botanická 68a, Brno, Czech Republic