Will our Universe expand forever, or there is a Big Crunch coming up? How can the rate of the Universe expansion be measured in a laboratory? How does the boundary of space look? How can Mach's principle be verified experimentally? How many stars are needed in order for the law of inertia to hold? What is a source of the uncertainty in the micro world? How does an indivisible electron contrive to pass through two holes at the same time? What mechanism underlies the gravitational interaction? Why is space-time curved near a large mass? What happens to an atom in a gravitational field? And, finally, where all these black holes go? If you want to know answers to these questions, this book is for you! In this book, the uncertainty and gravitation are considered as two aspects of the same phenomenon. The mechanism of the gravitational attraction is explained visually. A physical sense of the curved space-time is revealed on a simple example of an atom in a gravitational field. An explanation of the most bizarre quantum paradoxes as, for instance, the corpuscle-wave dualism and non-locality is proposed. A description of the experiment on measurement of the rate of the Universe expansion is presented.