Violation of CPT and Quantum Mechanics in the K0 - Anti-K0 System

We reconsider the model of quantum mechanics violation in the K 0 -K0 system, due to Ellis, Hagelin, Nanopoulos, and Srednicki, in which CP-and CPT -violating signatures arise from the evolution of pure states into mixed states.We present a formalism for computing time-dependent asymmetries in this model and show that present data constrains its parameters significantly.In the future, this model will be put to very stringent tests at a factory.We present the theory of these tests and show the relation between particular decay correlations and the parameters of quantum mechanics violation.