It does: Light does not follow the path of minimal distance between two points, but the path of minimal time. This is called Fermat’s principle.
Because water has a higher refraction index than air, light is slower in it and therefore takes a longer time to travel through it. Thus, it takes less time to take a longer path that spends more time in the air.
Fun fact: The underlying law of this principle is the principle of least action. This is the most basic law of nature we know of and can be used to derive all of physics.
The probably of the path it takes is the sum of all possible paths. Richard Feynman uses this exact swimmer in the water example during ok if his lectures.
I could resist the urge… But… Uh… The transcript incorrectly labels the symbol for capacitor, it’s actually the NEMA symbol for a contactor. Had to make sure I wasn’t sobbing my foot in my mouth. Capacitor symbol is extremely similar, but the right side needs to be bent like a parentheses foot it to be a capacitor like -|(-
I’m not positive but it might be due to the steps the Lemm.ee admin is taking to combat the CSAM uploads that have been happening and prevent the server’s administration team from being liable for potentially harmful and illegal images being hosted on their server.
I feel it’s a missed opportunity to exclude the ice cream sales and drowning deaths correlation, but that’s just me. I like the maximal time route goes up, though.
xkcd
Active