> Instead, for a safe, steady energy output, the pigments of the photosystem had to be very finely tuned in a certain way. The pigments needed to absorb light at similar wavelengths to reduce the internal noise. But they also needed to absorb light at different rates to buffer against the external noise caused by swings in light intensity. The best light for the pigments to absorb, then, was in the steepest parts of the intensity curve for the solar spectrum — the red and blue parts of the spectrum.
I admit there's a bit of a jump there (gotta read the actual article, not the journalist retelling I suppose), but I assume the gist of the math is something like this:
Lets say direct green light delivers a maximum 100 "units of photo-energy" -- gonna play loose with the physics to demonstrate the math.
When a cloud passes over it, lets say the intensity drops to only 75%. Lets also say for now we always convert the energy at 100% efficiency.
So with green light, your 100 units of energy drops by 25 units with each passing cloud.
Now lets say blue light delivers only 80 units of energy. When that same cloud passes over, 80 * 75% = 60 units of energy, or a drop of 20 units.
So, if your process is sensitive to changes in absolute energy, you would rather have a swing of 20 units for every passing cloud than a swing of 25 units. Yeah, you might get less absolute energy (60 units rather than 75), but if the cost of energy swings in your process was very high, the tradeoff might be worth it.
You could also play with the efficiency-of-conversion (ie have higher conversion efficiency at the lower-swing points) for some fun second-order effects.
This is just a toy example of what the underlying dynamics could be. Gotta read the actual paper to understand the actual model they developed. https://arxiv.org/pdf/1912.12281.pdf