:It may be that further categorizing is necessary. For example, issues like the Twin Paradox and the Ehrenfest Paradox are not strictly unobserved phenomena either. Item 37, failure to solve the equations, is a problem for mathematics, not necessarily for relativity. | :It may be that further categorizing is necessary. For example, issues like the Twin Paradox and the Ehrenfest Paradox are not strictly unobserved phenomena either. Item 37, failure to solve the equations, is a problem for mathematics, not necessarily for relativity. |