I'm not familiar with that particular paper, but I'm aware of a similar line of attack from a decade or so ago. Off the top of my head I can tell you that we kn

I'm not familiar with that particular paper, but I'm aware of a similar line of attack from a decade or so ago. Off the top of my head I can tell you that we know Riemann is provably false if it is false[1]. I'm not aware of any comparable result for the affirmative, but personally I'm a bit skeptical of the undecidability argument. That being said, it would be kind of narratively satisfying if Riemann is undecidable. There are many novel theorems from the past two decades which are conditionally true assuming Riemann is true. Riemann itself has become a useful technique for conditionally proving new theorem. If Riemann is undecidable, it would imply a great deal of mathematics has been developed which compartmentalizes the undecidability of other theorems. ______________________ 1. https://mathoverflow.net/questions/79685/can-the-riemann-hypothesis-be-undecidable https://mathoverflow.net/questions/79685/can-the-riemann-hyp...