The quantized spin component of a moving particle(noun)
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Use "helicity" in a sentence
"Also gravity waves have to directions of polarization, instead of one for EM waves, which is tied to something called helicity which is 2."
"In section 33.8, Penrose brings in "Massless fields of mixed helicity-such as a plane-polarized photon, which is the sum of a right-handed and left-handed part"."
"The photon has a helicity or spin, momentum and energy."