When light propagates in a dielectric its wavevector is given by:(adsbygoogle = window.adsbygoogle || []).push({});

[tex]

k = \frac{\omega n}{c}

[/tex]

where n is the refractive index. If light propagates in vacuum n=1 the momentum is [tex]\omega / c[/tex] but if light propagates in a dielectric of for example n=1.33 the momentum is increased beyond the value of the momentum in vacuum? Where does this extra momentum come from? It has to come from the dielectric somehow but how does this work?

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# Light hitting a dielectric, increase of momentum

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