FTP, name this German mathematician and  namesake for a four-dimensional space, the founder of space-time geometry.
His early interest in relativity stemmed from the fact that he had been  Albert Einstein's math teacher at the Zurich Technical School. Einstein  himself credited him with making possible the practical study of modern  physics, as it was he who added the fourth dimension to Euclidian geometry,  expressed in imaginary units. FTP, name this German mathematician and  namesake for a four-dimensional space, the founder of space-time geometry.
His early interest in relativity stemmed from the fact that he had been  Albert Einstein's math teacher at the Zurich Technical School.
Hermann {Minkowski}