Determine the physical upper bound of computation in our universe

Determine whether the set of functions that are physically computable in our universe coincides with the set of Turing-computable functions (the physical Church–Turing thesis), thereby identifying the true upper limit on what is physically computable.

Background

The paper frames its results around the physical Church–Turing thesis, which posits that the functions physically computable in our universe are exactly those computable by a Turing machine. The author explicitly notes that the true upper limit of physical computation is not established.

Resolving this question determines which class of Busy Beaver–type bounds would govern physically realizable rates of growth and convergence and clarifies whether the derived limits follow from actual physical law or from an incorrect premise about physical computability.