The two texts below suggest that, if the speed of light is variable (it is!), fundamental physics, entirely predicated on Einstein's constant-speed-of-light falsehood, is long dead (lives a kind of zombie life):

"He opened by explaining how Einstein's theory of relativity is the foundation of every other theory in modern physics and that the assumption that the speed of light is constant is the foundation of that theory. Thus a constant speed of light is embedded in all of modern physics and to propose a varying speed of light (VSL) is worse than swearing! It is like proposing a language without vowels." http://www.thegreatdebate.org.uk/VSLRevPrnt.html

"If there's one thing every schoolboy knows about Einstein and his theory of relativity, it is that the speed of light in vacuum is constant. No matter what the circumstances, light in vacuum travels at the same speed... The speed of light is the very keystone of physics, the seemingly sure foundation upon which every modern cosmological theory is built, the yardstick by which everything in the universe is measured. [...] The only aspect of the universe that didn't change was the speed of light. And ever since, the constancy of the speed of light has been woven into the very fabric of physics, into the way physics equations are written, even into the notation used. Nowadays, to "vary" the speed of light is not even a swear word: It is simply not present in the vocabulary of physics." https://www.amazon.com/Faster-Than-S.../dp/0738205257

Physicists know that the speed of light is variable and even start telling the truth sometimes but then stop halfway. Modern (zombie) physics is entirely predicated on Einstein's false constancy and will collapse without it. In this regard telling the truth is suicidal:

Joao Magueijo, Niayesh Afshordi, Stephon Alexander: "So we have broken fundamentally this Lorentz invariance which equates space and time [...] It is the other postulate of relativity, that of constancy of c, that has to give way..." https://youtu.be/kbHBBtsrU1g?t=1431

"Lee [Smolin] and I discussed these paradoxes at great length for many months, starting in January 2001. We would meet in cafés in South Kensington or Holland Park to mull over the problem. THE ROOT OF ALL THE EVIL WAS CLEARLY SPECIAL RELATIVITY. All these paradoxes resulted from well known effects such as length contraction, time dilation, or E=mc^2, all basic predictions of special relativity. And all denied the possibility of establishing a well-defined border, common to all observers, capable of containing new quantum gravitational effects." Joao Magueijo, Faster Than the Speed of Light, p. 250 http://www.amazon.com/Faster-Than-Sp.../dp/0738205257

"[George] Ellis is up against one of the most successful theories in physics: special relativity. It revealed that there's no such thing as objective simultaneity. [...] Rescuing an objective "now" is a daunting task." https://www.newscientist.com/article...wards-in-time/

"The whole of physics is predicated on the constancy of the speed of light," Joao Magueijo, a cosmologist at Imperial College London and pioneer of the theory of variable light speed, told Motherboard. "So we had to find ways to change the speed of light without wrecking the whole thing too much." https://motherboard.vice.com/en_us/a...t-speed-slowed

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