Contrary to popular believe, there are many Schwarzschild Solutions. Karl himself found one to a mass-point and one to a sphere of in-compressible liquid early 1916. After Karl’s death Einstein made important changes in his  official publication: he abandoned his g = -1 requirement in a footnote. Nobody checked...

After publication in 1905 of his Special Relativity, Einstein was praised but he also got a lot of criticism. Paul Ehrenfest, Mach and others revealed inconsistencies. Einstein listened to them and made crucial improvements in 1916 so that the famous paradoxes disappeared. It formed the basis for his General...

How many people understand Relativity? Many say they do, but how do they explain the paradoxes of Special Relativity (SR)? Do they know that Einstein changed his mind about his own SR in 1916? They should know that he abandoned the equality of reference frames already in 1916, solving the twin paradox. Then Einstein...

In 1908 Hermann  Minkowski improved Special Relativity Theorie by replacing the Lorentz transformation by his own differential formula. Einstein followed him because now the speed of the proper observer could vary. Later Einstein made use of Minkowski’s formula in his General Relativity. Another advantage was that the...

In his Theory of General Relativity, Einstein replaced the Lorentz transformation by the formula of his tutor Minkowski. What happens if we apply the Minkowski formula back into the Theory of Spécial Relativity? What are the differences? This article shows: the Minkowski’s formula doesn’t create the Twin- and Ehrenfest...

In his theory of General Relativity, Einstein replaced the Lorentz transformation by the Minkowski formula. He also introduced the variable speed of light in gravitation. This is unnecessary and untenable: it is  in conflict with Noether’s theorem on energy and momentum conservation. The authors use the ‘time’...