Spaces vector semispace

A Vector Semispace (VSS) over the PD real field R, is a Vector Space (VS) with the vector sum part provided by a structure of abelian semigroup. ... 

Mezey, Eds., JAI Press, London, 1998, pp. 43-72. Fuzzy Sets and Boolean Tagged Sets Vector Semispaces and Convex Sets Quantum Similarity Measures and ASA Density Functions Diagonal Vector Spaces and Quantum Chemistry. 

A vector semispace is a vector space without reciprocal elements and iJius defined over the positive real field. 

A vector semispace is considered here as a vector space defined over the positive real numbers. In this way the additive group of the semispace is a semigroup, a group without reciprocal elements. DF sets like the quantum object tags already discussed in MQOS definition are subsets of some Hilbert semispace. 

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