How big is a visible photon?

In this video I discuss the behavior of photons/electromagnetic waves especially the aspect of interference. At the same time, I wanted to set an error straight that was presented in a previous video. The video involved (“Photons in Radio Waves and Visible Light“, ) contained a mis-intepretation of the observed phenomenon. The current video not only exposes the flaw, but presents a better explanation. 0:00 General Intro 0:47 What do others say? 1:21 About wavelength and size 2:10 Interference in light 3:08 Electromagnetic waves and detection 5:25 Things that make you go Hmmm... 7:36 New experiment and setup 10:23 Calculation of single photon level (boring) 11:59 Result of the new experiment 12:41 Discussion of the result 16:29 About “shot noise“ 17:16 EM field strength and probability of detection 19:18 So how big is it then? 20:02 Deleted scene Thanks to David Nadlinger, I was able to put my finger on what was experimentally wrong with the original experiment . The scientific explanation is actually very mathematical and way more complex: And although scientifically not very accurate, I tried to present a more intuitive description, based more on the classical description of EM waves rather than trying to explain the second order coherence function. More about shot noise: The “deleted scene“ contains a 4 second clip of the movie “Crash Pad“ (For preview see: It also contains a short audio clip of “New York City“ by the Trammps ( I would also like to thank Vicky Pollard for explaining Quantization in more detail. These clips constitute copyrighted material, the use of which has not been specifically authorized by the copyright owner. The material serves as an educational and entertaining resource and only small portions of the original work are being used. This should constitute a ’fair use’ of any such copyrighted material (referenced and provided for in section 107 of the US Copyright law). If you wish to use any copyrighted material from this video for purposes of your own that go beyond ’fair use’, you must obtain expressed permission from the copyright U.S. Code § 107 Do you like what I do and want to support it? I’v recently started a patreon page: