Quantum Yang-Mills theory, Classical Statistical Field Theory (for Hamiltonians which are non-polynomial in the fields, e.g. General relativistic statistical mechanics) and Quantum Gravity all suffer from severe mathematical inconsistencies and produce unreliable predictions at best.
We define a class of statistical field theories where the probability distribution of the infinite-dimensional phase-space is mathematically defined by a wave-function in a Fock-space, allowing Hamiltonians which are non-polynomial in the fields. In this formalism, the wave-function is crucial already for classical statistical field theory due to mathematical reasons.
It was often claimed that the mathematical inconsistencies only affect Field Theory and spare Quantum Mechanics (which would only suffer a mild interpretation ambiguity) but here we show that instead the mathematical inconsistencies from Field Theory do have collateral consequences for the ensemble interpretation of Quantum Mechanics (where Quantum Mechanics merely describes a statistical ensemble of objects and not individual objects).
We also show that for a quantum system defined in a 2-dimensional real Hilbert space, the role of the (2-dimensional real) wave-function is identical to the role of the Euler's formula in engineering, while the collapse of the wave-function is identical to selecting the real part of a complex number; the collapse of the wave-function of any quantum system is a recursion of collapses of 2-dimensional real wave-functions.
We then define a subclass of statistical field theories in Minkowski space-time where the (classical) canonical coordinates when modified by a non-deterministic time evolution, verify the canonical commutation relations. By defining gauge symmetries through algebraic ideals, we propose definitions for Quantum Yang-Mills and Quantum Gravity. Finally, we test the consistency of our formalism with the quantization of the free Electromagnetic field.
*Chapters ending with an * symbol address foundational questions and can be skipped in a first reading.