3 ms·
Yeah I was also surprised to find that photons can be really big: https://youtu.be/SDtAh9IwG-I https://youtu.be/SDtAh9IwG-I Before I saw the experiments in tha
by NavinF 5y ago
Yeah I was also surprised to find that photons can be really big: https://youtu.be/SDtAh9IwG-I https://youtu.be/SDtAh9IwG-I
Before I saw the experiments in that video, I assumed photons were about as wide as their wavelength.
- BobbyJo 5y agoWoah. Thank you. This is nuts.
- nazgulnarsil 5y agoamazing video. thanks.
- Maursault 5y agoThat guy is hilarious.[1][2][3] I'd like to know what would happen if the split beam was sent through fibre optics to Pluto and back, if the interference pattern would persist instantly. [1] "It's a golden oldie..." [2] "... just to give the setup a nice high tech look and feel." [3] "The physics behind this is pretty hefty, and not, like, youtube video material."
- baq 5y agoFrom what little I know about quantum mechanics, the statement about changing the light source and expecting to not see an interference pattern is very surprising. I’d expect to see one.
- superjan 5y agoYes, pity that is not in the video.
- jlokier 5y agoDifferent light sources emit with different "Coherence length". A continuous-wave laser has high coherence length, and a light source that isn't a laser at all has low coherence length even if it's monochromatic, for example a sodium lamp. The laser used by the presenter has a coherence length longer than (or in the same ballpark as) the difference in optical paths in their experiement, so they get a clear interference pattern. The Wikipedia article may explain. https://en.wikipedia.org/wiki/Coherence_length https://en.wikipedia.org/wiki/Coherence_length Since you can measure coherence length (and higher-order temporal and spatial coherence statistics), it is part of the information carried by light from a luminous object that is available for imaging by a suitably designed camera.