If one takes seriously the postulate of quantum mechanics in which physical states are rays in the standard Hilbert space of the theory, one is naturally lead to a geometric formulation of the theory. Within this formulation of quantum mechanics, the resulting description is very elegant from the geometrical viewpoint, since it allows to cast the main postulates of the theory in terms of two ge...

The requirement that memory he superposition-free imposes a restrictive condition on the structure of neural models. A simple model which satisfies this condition consists of two levels of neurons, with primary level neurons tiring in response to external input and secondary (reference) neurons modifying activated primaries in such a way that they can later fire these primaries. Reference neuro...