Smarandache Multi-Space Theory(I)-Algebraic multi-spaces
  A Smarandache multi-space is a union of $n$ different spaces equipped with some different structures for an integer $n\geq 2$, which can be both used for discrete or connected spaces, particularly for geometries and spacetimes in theoretical physics. This paper is the first part on characterizing multi-spaces. Various algebraic multi-spaces with structures such as those of multi-groups, multi-rings, multi-vector spaces, multi-metric spaces, multi-operation systems are discussed and new results are obtained. 
Linfan Mao