I read that to mean "uses [a] physics", meaning a specific reaction chain, not physics the entire field. Kind of like talking about "battery chemistry" meaning

I read that to mean "uses [a] physics", meaning a specific reaction chain, not physics the entire field. Kind of like talking about "battery chemistry" meaning Li-based, Pb-based, etc., does not mean "the field of chemistry". Could it have been worded better? Sure.