FYI:

"The foundational problems of quantum mechanics (Ph2): These problems concern the fundamental understanding of quantum physics and especially

the important role that measurement and observation play in the description ofphysical reality. There are currently many interpretations of quantum physics,

including the classic Copenhagen interpretation, Everett’s controversial “many worlds” interpretation, and even more controversial ones such as the “participatory anthropic principle”.

In particular,

1.

how does the quantum interpretation of reality, which includes the superposition of states and wavefunction collapse or quantum decoherence, give rise to what we perceive?2.

What are the actual causes of the collapse of the quantum wavefunction? 3.

Are there non-local phenomena in quantum physics and, if they do in fact exist, are they limited to the entanglement revealed in the violations of the Bell inequalities and can they be observed? 4.

What does the existence or absence of non-local phenomena imply about the fundamental structure of spacetime and how is this related to quantum entanglement? Most modern physicists who work within quantum field theory perhaps no longer consider questions of the proper interpretation of the fundamental nature of

quantum physics to be of prime importance. Indeed, many may believe that the principle of decoherence is essentially an appropriate explanation; for example,

interaction with the environment causes the quantum collapse. However, dynamical models have been proposed to explain the collapse of

the wave-function and perhaps provide a possible solution to the quantum measurement problem, by proposing that the Schrodinger equation is an approximation to a stochastic nonlinear dynamics (with the stochastic nonlinear aspect becoming increasingly more important when progressing from microscopic systems to macroscopic ones) [158]. In addition, as in most other physical systems, evolution in time is central to the understanding of quantum systems. The time that is used to define evolution in quantum theory is clearly part of the classical spacetime manifold. However, this perhaps suggests that (5.)

the present formulation of quantum theory is incomplete and that there ought to exist a reformulation of quantum theory which does not refer to classical time."

Source: '

Open problems in mathematical physics' by Prof. A. A. Coley.