URGENT

THE FIRST DIRECT MEASUREMENT OF RECOIL MOMENTUM for single atoms
struck by light in an absorptive medium has been made by Gretchen
Campbell, Dave Pritchard, Wolfgang Ketterle and their colleagues at
MIT. Parcels of light, photons, do not possess mass, but a beam of
light does carry momentum. In general, when light strikes a mirror,
the mirror will recoil ever so slightly, and this recoil has
previously been measured. But what about a single photon striking a
single atom in a dilute gas? The momentum of a photon equals
h/lambda, where h is Planck's constant and lambda is the wavelength
of the light in vacuum. In a dispersive medium, a medium which can
scatter or absorb light, the index of refraction for the medium, n,
comes into play: an object absorbing the photon will recoil with a
momentum equal to nh/lambda. This is what has been measured for the
first time on an atomic basis. The MIT team used laser beams sent
into a dilute gas; a beat note between recoiling atoms and atoms at
rest provided the momentum measurement of selected atoms. The fact
that the recoil momentum should actually be proportional to the
index of refraction came as something of a surprise to the
experimenters.

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The existence of momentum without mass is a stunning observation that opens the door to an unfathomable array of new BS.

Not to mention mirrors flinching from incident light rays. I submit tha if the light waves striking the mirror are harmoniously related (as when something of beauty stands before the glass) the mirror will flinch less than if discordant (and therefore ugly) rays are involved.

Please test this theory out and get back to me.

I can't test it myself as all our mirrors here have been leaping out of windows and breaking.


A