The motion of electrons in superconductors seems to exceed our imagination based on daily experience with Newtonian mechanics. This book shows that the classical concepts, such as the balance of forces acting on electrons, are useful for understanding superconductivity. The electrostatic field plays a natural part in this balance as it mediates forces between electrons at long distances.

There are many monographs and textbooks addressing superconductivity from di?erent angles. In spite of a large variety of explored approaches, one problem is always left aside. It is the balance of forces acting on the sup- conducting condensate. In the present book this question is central. As the title suggests, there is a close analogy between the electrostatic ?eld in superconductors and the pressure in the ideal incompressible liquid. As one can easily imagine looking at swirling water, molecules of the inc- pressible liquid are accelerated by gradients of the pressure so that they can...