Einsteinians are practitioners of doublethink - they both worship and reject some concept so that the gullible world can come to the conclusion that in science thesis and antithesis harmoniously coexist. The champion is undoubtedly Steven Jonathan Carlip, professor of physics at the University of California, Davis. Carlip is a practitioner of triple- and even quadruplethink. A synopsis of his teaching: The speed of light is constant by definition.. Einstein said the speed of light is variable in a gravitational field - an interpretation which is perfectly valid and makes good physical sense - but later the speed of light in general relativity became constant. So constant that "it does not even make any sense to say that it varies". Finally, in a gravitational field, light falls with twice the acceleration of ordinary falling matter:

Steve Carlip: "Is c, the speed of light in vacuum, constant? At the 1983 Conference Generale des Poids et Mesures, the following SI (Systeme International) definition of the metre was adopted: The metre is the length of the path travelled by light in vacuum during a time interval of 1/299 792 458 of a second. This defines the speed of light in vacuum to be exactly 299,792,458 m/s. This provides a very short answer to the question "Is c constant": Yes, c is constant by definition! [...] Einstein went on to discover a more general theory of relativity which explained gravity in terms of curved spacetime, and he talked about the speed of light changing in this new theory. In the 1920 book "Relativity: the special and general theory" he wrote: "...according to the general theory of relativity, the law of the constancy of the velocity of light in vacuo, which constitutes one of the two fundamental assumptions in the special theory of relativity [...] cannot claim any unlimited validity. A curvature of rays of light can only take place when the velocity of propagation of light varies with position." Since Einstein talks of velocity (a vector quantity: speed with direction) rather than speed alone, it is not clear that he meant the speed will change, but the reference to special relativity suggests that he did mean so. This interpretation is perfectly valid and makes good physical sense, but a more modern interpretation is that the speed of light is constant in general relativity. [....] Finally, we come to the conclusion that the speed of light is not only observed to be constant; in the light of well tested theories of physics, it does not even make any sense to say that it varies."

http://www.desy.de/user/projects/Phy..._of_light.html
Steve Carlip: "It is well known that the deflection of light is twice that predicted by Newtonian theory; in this sense, at least, light falls with twice the acceleration of ordinary "slow" matter."

https://arxiv.org/pdf/gr-qc/9909014v1.pdf
https://i0.wp.com/www.wakeupkiwi.com...sonalities.jpg
Pentcho Valev