Hello everyone, This Wednesday 29.11.2023 at 13:30 in room D5.01 we'll have a forum. The plan is to hear a double-feature: first an extended technical talk by Alberto (title and abstract below) followed by "an open floor on cryptography and crypto currencies: can technology be used -- and which -- to build a free society?", initiated and moderated by Stefan. Anyone else who would like to speak afterward is welcome. It can be of any length on any subject, even something spontaneous -- we have the room for the whole afternoon. Join us in person or online at https://meet.jit.si/CQISeminarTalks Warm regards, Will Schober Title: classical Markov simulations of quantum processes and the reality of the wave-function. Abstract: In this talk, I will consider classical Markov simulations of quantum processes and I will show that the state space of the simulation must contain a Hilbert space of the same dimension of the Hilbert space associated with the simulated quantum system and, furthermore the evolution is described by the same unitaries. In particular, this model of simulation must have an exponential computational complexity. The result is quite close to the pbr proof, but it uses a much milder hypothesis.