The universe decisively shifts - space and time amalgamate and squirm together - so that the constant-speed-of-light nonsense can become an absolute non-negotiable:

John Stachel: "But this seems to be nonsense. How can it happen that the speed of light relative to an observer cannot be increased or decreased if that observer moves towards or away from a light beam? Einstein states that he wrestled with this problem over a lengthy period of time, to the point of despair." http://www.aip.org/history/exhibits/...relativity.htm

Michelle Thaller: "All of the universe shifts around this constant, the speed of light" https://youtube.com/watch?v=DO7J2YIz8tY

Brian Greene: "Einstein proposed a truly stunning idea - that space and time could work together, constantly adjusting by exactly the right amount so that no matter how fast you might be moving, when you measure the speed of light it always comes out to be 671000000 miles per hour." https://www.youtube.com/watch?v=dc3-29dguFs

Brian Greene: "If space and time did not behave this way, the speed of light would not be constant and would depend on the observer's state of motion. But it is constant; space and time do behave this way. Space and time adjust themselves in an exactly compensating manner so that observations of light's speed yield the same result, regardless of the observer's velocity." http://www.pbs.org/wgbh/nova/physics...-nutshell.html

Neil deGrasse Tyson, Death by Black Hole: And Other Cosmic Quandaries, pp. 123-124: "If everyone, everywhere and at all times, is to measure the same speed for the beam from your imaginary spacecraft, a number of things have to happen. First of all, as the speed of your spacecraft increases, the length of everything - you, your measuring devices, your spacecraft - shortens in the direction of motion, as seen by everyone else. Furthermore, your own time slows down exactly enough so that when you haul out your newly shortened yardstick, you are guaranteed to be duped into measuring the same old constant value for the speed of light. What we have here is a COSMIC CONSPIRACY OF THE HIGHEST ORDER." https://www.amazon.com/Death-Black-H.../dp/039335038X

"At a time when other scientists believed that the speed of light was variable, Einstein took it as a fixed limit of nature and made it the absolute non-negotiable around which all other variables and parameters enfolded."
https://www.brainpickings.org/2019/0...ng-relativity/

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