Preface
All phenomena in nature are characterized by motion. Mechanics deals with the
objective laws of mechanical motion of bodies, the simplest form of motion.
In the study of a science of nature, mathematics plays an important rôle. Mechanics
is the first science of nature which has been expressed in terms of mathematics, by
considering various mathematical models, associated to phenomena of the surrounding
nature. Thus, its development was influenced by the use of a strong mathematical tool.
As it was already seen in the first two volumes of the present book, its guideline is
precisely the mathematical model of mechanics. The classical models which we refer to
are in fact models based on the Newtonian model of mechanics, that is on its five
principles, i.e.: the inertia, the forces action, the action and reaction, the independence
of the forces action and the initial conditions principle, respectively. Other models, e.g.,
the model of attraction forces between the particles of a discrete mechanical system, are
part of the considered Newtonian model. Kepler’s laws brilliantly verify this model in
case of velocities much smaller then the light velocity in vacuum.
Mechanics has as object of study mechanical systems. The first two volumes of this
book dealt with particle dynamics and with discrete and continuous mechanical
systems, respectively. The present one deals with analytical mechanics. We put in
evidence the Lagrangian and the Hamiltonian mechanics, where the study of first
integrals plays a very important rôle. The Hamilton–Jacobi method is widely
considered, as well as the study of systems with separate variables. We mention also a
thorough study of variational principles and canonical transformations. The symmetry
transformations, including Noether’s theorem, lead to conservation laws. Integral
invariants and exterior differential calculus are also included. A particular attention has
been given to non-holonomic mechanical systems. Problems of stability and vibrations
have been also considered in the frame of Lagrangian and Hamiltonian mechanics. The
study of dynamical systems leads to catastrophes, bifurcations and chaos.
One presents some applications connected to important phenomena of the nature and
one gives also the possibility to solve problems presenting interest from technical,
engineering point of view. In this form, the book becomes – we dare say – a unique
outline of the literature in the field; the author wishes to present the most important
aspects related with the study of mechanical systems, mechanics being regarded as a
science of nature, as well as its links to other sciences of nature. Implications in
technical sciences are not neglected.
Concerning the mathematical tool, the five appendices in the first volume give the
book an autonomy with respect to other works, special previous mathematical
knowledge being not necessary. The numeration of the chapters follows that of the first
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