The essential points of this ?rst chapter are - The de?nition of a complex system - The notion of emergence - The de?nition of a model - The notion of dynamical system This book is about the dynamics of complex systems. Roughly speaking, a system is a collection of interacting elements making up a whole such as, for instance, a mechanical clock. While many systems may be quite complicated, they are not necessarily considered to be complex. Today, most authors agree on the essential properties a system has to possess to be called complex. The ?rst section is devoted to the description of these properties. To interpret the time evolution of a system, scientists build up models, which are simpli?ed mathematical representations of the system. The exact purpose of a model and what its essential features should be is explained in the second section. The mathematical models that will be discussed in this book are dynami- 1 calsystems. A dynamical system is essentially a set of equationswhose- lutiondescribesthe evolution,asafunction oftime, ofthe state ofthe system. There exist di?erent types of dynamical systems. Some of them are de?ned in the third section. 1 There is an extensive literature on mathematical modeling. The reader may, for example, consult [11,88,163,233].
From the reviews of the second edition:
"Boccara's approach is firmly based on dynamical systems theory, differential equations, and maps, with a very solid mathematical treatment, cast at times in terms of definitions and theorems. ... The book is very well suited for graduate or advanced undergraduate studies and comes with a problem and solution section at the end of every chapter. ... The book covers in any case a plethora of models and is highly recommendable for everybody wishing to attain a good knowledge of classical complex system theory." (Claudius Gros, SIAM Review, Vol. 53 (4), 2011)
"Boccara's approach is firmly based on dynamical systems theory, differential equations, and maps, with a very solid mathematical treatment, cast at times in terms of definitions and theorems. ... The book is very well suited for graduate or advanced undergraduate studies and comes with a problem and solution section at the end of every chapter. ... The book covers in any case a plethora of models and is highly recommendable for everybody wishing to attain a good knowledge of classical complex system theory." (Claudius Gros, SIAM Review, Vol. 53 (4), 2011)