Theory 78/Energy Limits/Photosynthesis
Photosynthesis Has a Ceiling
The claim
Photosynthetic efficiency is capped by the ratio of usable to absorbed photons, and the cap is set by the spectrum rather than by the enzyme.
01Mechanism
Photons below the band gap are wasted and those above lose excess as heat; the fraction usable sets the ceiling before any biochemical limitation.
02Prediction
Efficiency should track the spectral ratio across light sources.
03Refutation
Efficiency tracking enzyme capacity would remove the spectral limit.