It is difficult to phrase an answer depending on what is understood with as “proven”. As I was made aware in my lectures, axioms are considered truthful statements that are empirically observed and don’t require proof respectively can’t be proven (at least as of yet). However, there may be more than one “truth” statement to describe the same observations of a system (e.g mechanics with Newtonian or Lagrangian). If one considers the fact that the axioms correctly describe and predict observation, it can be considered a proven truth but this however doesn’t constitute as a proof in the mathematical sense.