Observables on synaptic algebras

Synaptic algebras, introduced by D. Foulis, generalize different algebraic structures used so far as mathematical models of quantum mechanics: the traditional Hilbert space approach, order unit spaces, Jordan algebras, effect algebras, MV-algebras, orthomodular lattices. We study sharp and fuzzy observables on two special classes of synaptic algebras: on the so called generalized Hermitian algebras and on synaptic algebras which are Banach space duals. Relations between fuzzy and sharp observables on these two types of synaptic algebras are shown. (C) 2020 Elsevier B.V. All rights reserved.