Err, no! "Bright" sunlight has more photons, not heavier ones.
Shorter wavelength (bluer) photons _are_ heavier (*) and impart more momentum when they stop.
*: Well, the "weight" of a photon is slightly complex. Photons have zero rest mass, but they have mass from their energy (E=mc^2).
WHoooosh
Is that a I don't understand the concept of a particle travelling at the speed of light having a finite mass, or a whoosh for not understanding how a Crookes Radiometer works? Or both?
I think it's a whoosh at the implication that it spins in one direction because the bright photos push harder on the white side than the dark photons push on the black side :-P
I think its a whoosh for not realising that the author also understood both, and was joking.
A case of being so far ahead you turned round and saw him behind you. Its relativity.
Since they are moving (and have zero rest mass), you need to include the momentum term in the slightly longer version of the equation:
E^2 = (mc^2)^2 + (pc)^2
We are using slightly different meanings of "mass" here.
The 'm' in your equation is m0 - the rest mass. The 'm' in my equation is the effective (gravitational) mass.
A photon exerts a gravitational pull on the rest of the universe, and the strength of that pull is given by the mass = E/c^2.
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