
Ask HN: Why crossing light beams don't collide/decrease each other's brightness? - tarikozket
Why light doesn&#x27;t interact or interfere with another light? For instance: http:&#x2F;&#x2F;mrclarkrbhs.wikispaces.com&#x2F;file&#x2F;view&#x2F;galarie_psl.jpg&#x2F;339906824&#x2F;440x277&#x2F;galarie_psl.jpg
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mysterymachine
Light does experience interference, but in a wavelike manner, not a purely
additive manner. Here's what wikipedia has to say.

[https://en.wikipedia.org/wiki/Interference_(wave_propagation...](https://en.wikipedia.org/wiki/Interference_\(wave_propagation\)#Optical_interference)

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ctdonath
Same reason a room doesn't get quieter when lots of people are talking.

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philipov
Because photons are massless and behave like waves.

