Oh boy, Merl, I came ready for a fight today!
Almost got one, except I took a few extra minutes....
OK, what I might have better said yesterday (still equally wrong, of course) is that Period is Wavelength. And YOUR graph shows just that.
But, Period is not a distance, is it? it is a cycle, a repetition, like "tick-tock, tick-tock...?" and wavelength is actual (physical) distance between "ticks" (or tocks).
Good gawd, I should have known that. I do know that.... oh bother.
So, your graph is a 4Hz frequency; if it's a light wave, the lambda (wavelength) is (3.0^8 m/s) / (4 Hz) = 7.5^7 meters.
Then we put it in Harvard's sodium decelerator, frequency doesn't (can't) change L = (610,000 m/s) / (4 Hz) = waves are scrunched to 152,500 meters.
OK, I calmly accept my defeat. Now, tell me, when these light waves peaks are getting closer together due to deceleration, will amplitude increase? (I'm thinking like tsunami wave coming ashore...wave slows, wave rises).
And, now that I'm thinking about it (stupid mathematics, anyway), what exactly does a "stopped" wave look like L = (0 m/s) / (4Hz) = 0 meters?? Does a stopped have a frequency? Or, if it's stopped, it's not a wave, so wave-functions / terminology no longer apply?
That last one is probably it, since they say "effectively turning light into matter." OK, then how much does it weigh?