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Einstein explicitly wrote this for those without advanced mathematical training, using only high-school algebra to illustrate his points. Relativity: The Special and the General Theory,...
The book is divided into three main parts that build from the basics of motion to the grand structure of the cosmos: Because the original work is in the public
This section expands relativity to include gravity. Einstein describes gravity not as a force between objects, but as a curvature of spacetime caused by mass and energy. He uses the "Principle of Equivalence" to show that being in a gravitational field is indistinguishable from accelerating. Relativity: The Special and the General Theory,...