This book deals with some perennial problems in nuclear physics originating from the traditional picture of the nucleus as a classical liquid drop. It has introduced a relatively new model called Infinite Nuclear Matter Model in which the classical liquid has been replaced by quantum mechanical many-fermionic liquid in accord with the true nature of the matter contained in the nucleus. The model is based on a many-body theoretic foundation with the generalized Hugenholtz-Van Hove theorem playing the pivotal role. Thus the two main features of nuclear dynamics namely, the liquid and shell features are taken into account non-perturbatively at a microscopic level. Besides solving the long standing problem of the saturation properties of infinite nuclear matter using the nuclear masses only leading to the resolution of r0 -paradox, it has succeeded in determining the incompressibility in a more or less model independent manner following an Ab initio method with the input of nuclear ground state properties only. The model has given rise to a mass formula for nuclei with unique success in predicting unknown masses and unraveling new nuclear phenomena.