Is Turing's Thesis the Consequence of a More General Physical Principle?
  We discuss historical attempts to formulate a physical hypothesis from which Turing's thesis may be derived, and also discuss some related attempts to establish the computability of mathematical models in physics. We show that these attempts are all related to a single, unified hypothesis. 
Matthew P. Szudzik (Carnegie Mellon)
math.LO cs.CC cs.LO math-ph math.MP