Deformation Expression for Elements of Algebras (I) --(Jacobi's theta   functions and *-exponential functions)--
  This paper presents a preliminary version of the deformation theory of expressions of elements of algebras. The notion of *-functions is given. Several important problems appear in simplified forms, and these give an intuitive bird's-eye of the whole theory. 
Hideki Omori, Yoshiaki Maeda, Naoya Miyazaki, Akira Yoshioka
math-ph math.MP