So this is basically What happens to the energy when waves perfectly cancel each other? again, but I'm not understanding the answers given (or they don't address what I am confused about)
Basically given that waves can be reflected one could conceivably reflect two waves so that perfectly cancel each other out (I do not mean standing wave, I mean reflected so they end up going in the same direction and are "off" by exactly half a wavelength)
Suppose that we have 2 sources of same frequency light aimed directly at each other call this line l horizontal, and let P be a plane containing l and consider a perfectly reflective square (or cube ) S contained in P oriented 45 degrees to l and intersecting l on 2 adjacent sides of S so that the 2 light sources are perpendicularly reflected (in same direction) now slide the square S perpenticularly to l so that l intersects l at a single point p \in l. Now we have a way to "combine" 2 waves that are not in the same direction and we can choose p so that the two waves are "precisely" out of sync and cancel perfectly.
Of course I mean ignoring quantum / wave particle duality loss of heat/friction etc
Perhaps one should visualize this instead as sound waves bounced perfectly so they cancel out or..
@ACuriousMind while this could just be a comment on a different thread my comment did not recieve any attention, thus I decided to make it another topic
