(An ex-physicist here) Quantization of measured energy levels in a bound system has nothing to do with the potential discontinuity of spacetime. The latter is hypothesized, but by no means proven or even tested. As for the original quote, it states that one has to leave room for models other than “a discrete causal graph”.
(Another non-physicist here) I thought quanta were the living proof that on a fundamental level the universe was discontinuous.
(An ex-physicist here) Quantization of measured energy levels in a bound system has nothing to do with the potential discontinuity of spacetime. The latter is hypothesized, but by no means proven or even tested. As for the original quote, it states that one has to leave room for models other than “a discrete causal graph”.
The position operator has a real valued spectrum.