Einsteinian Contradictions 2

Einstein expressed his relation to mathematics as follows:

• Do not worry too much about your difficulties in mathematics, I can assure you that mine are still greater.
• So far as the theories of mathematics are about reality, they are not certain; so far as they are certain, they are not about reality.
• Since the mathematicians have invaded the theory of relativity, I do not understand it myself any more.

Despite his difficulties with mathematics, Einstein's tool as physicist was mathematics, with his general theory of relativity based on the difficult mathematics of differential geometry with its tensors, metrics, invariants, mappings and coordinates.

Einstein's math teacher the great mathematician Minkowski called him a "lazy dog", and Einstein had to rely on the help of his friend Grossmann, mathematician but not physicist.

The mystery, or greatness, or contradiction, of Einstein's work is captured in the second quote with its comparison between mathematics and physics. Einstein here refers to the fact that he is 100% sure that his special and general theories of relativity "are certain" since they "are not about reality", only about a postulated Einsteinan view of reality, which cannot be false by definition.

The basic example is the Lorentz transformation as the basis of the special theory of relativity, postulating how to measure space and time depending on observer velocity. As acknowledged by Einstein's friend Max Born, special relativity has no physical model and thus is not about reality:

• Length contraction and and time dilation (of special relativity) are ways of regarding things and do not correspond to reality.

Einstein made a free mix of physics about reality with mathematics not about reality, which gave him world fame time based on contradictions, as developed in more detail in Dr Faustus of Physics.
But did Einstein ever understand general relativity?

PS An example of the confusion created by Einstein with definitions being mixed up with statements about physics, is given in a recent post by Lubos, who after a lengthy response to a comment by me refuses further discussion.