Quantum-like structure is present practically everywhere. Quantum-like
(QL) models, i.e. models based on the mathematical formalism of quantum
mechanics and its generalizations can be successfully applied to
cognitive science, psychology, genetics, economics, finances, and game
theory.
This book is not about quantum mechanics as a physical theory. The short
review of quantum postulates is therefore mainly of historical value:
quantum mechanics is just the first example of the successful
application of non-Kolmogorov probabilities, the first step towards a
contextual probabilistic description of natural, biological,
psychological, social, economical or financial phenomena. A general
contextual probabilistic model (Växjö model) is presented. It can be
used for describing probabilities in both quantum and classical
(statistical) mechanics as well as in the above mentioned phenomena.
This model can be represented in a quantum-like way, namely, in complex
and more general Hilbert spaces. In this way quantum probability is
totally demystified: Born's representation of quantum probabilities by
complex probability amplitudes, wave functions, is simply a special
representation of this type.