Advances in Conception about Earthquakes - Earthquake Engineering for Structural Design - page 116

remains in motion until a force starts acting on the body. The second law, F = Ma,
equates the force with the rate of change momentum. The third law states that for
each action there is an equal and opposite reaction. These three laws are as
insightful as they are simple. Even today, in the results of more recent mechanical
theories, such as quantum mechanics and relativistic mechanics, the Newtonian
Laws are very widely used. It is very hard to overstate the importance of Newton's
contributions to the advancement of the science (Sell and You, 2002).
Newton introduced the concept of determinism , because his laws imply that
anything which happens at any future time is completely determined by what
happens now, and moreover that everything now was completely determined by
what happened at any time in the past. The determinism is the philosophical
proposition stating that every event is causally determined by an unbroken chain of
prior occurrences (Wikipedia, nd). According to the deterministic model of
science, the universe unfolds in time like the working parts of a perfect machine,
without randomness or deviation from the predetermined laws .
“… We may regard the present state of the universe as the effect of its past and
the cause of its future. An intellect which at any given moment knew all of the
forces that animate nature and the mutual positions of the beings that compose it,
if this intellect were vast enough to submit the data to analysis, could condense
into a single formula the movement of the greatest bodies of the universe and that
of the lightest atom; for such an intellect nothing could be uncertain and the future
just like the past would be present before its eyes.” (Laplace) (Gioncu, 2005)
This intellect has been later dubbed as Laplace's Demon (Garrette, 2003).
In the last time the Newtonian paradigm is contested by the new developments
in the System Theory.
The first doubt about the universality of the Newtonian paradigm comes from
the Thermodynamics Laws, which introduce the time as an important parameter in
the study of systems. Contrary to the Newtonian concept, where all the phenomena
are reversible, in Thermodynamics the most important characteristic is the
irreversibility.
Secondly, Leibnitz's aphorism:
“Natura non facit saltum” (Nature does not make jump)
based on the Newtonian paradigm, is denied by the surrounding reality,
characterized by sudden changing, discontinuous variations or mutations. Even the
earthquake events cannot be framed in the phenomena which respect the
Newtonian paradigm. Therefore, now it is widely understood that:
“Natura facit saltum” (Nature makes jump).
Studying these phenomena, Prigogine (during the 1970s) introduced a new
paradigm about the nonlinear behavior of Thermo-dynamical Systems (Prigogine
and Stengers, 1979). The behavior of a complex system is presented in Figure 4.10,