In the book "The Theory of Relativity", Albert Einstein and his assistant Alice explain to children the strange things that happen in the universe. It is not easy to understand that time, space and even mass are not something constant - they depend on the observer and reference systems! But here all this is told very simply. Thanks to clear examples and visual illustrations of experiments, even younger schoolchildren will be able to understand the world of relativity. The "About Science" series also includes the books "Quantum Physics" and "Architecture".