The Cosmological Constant for the Crystalline Vacuum Cosmic Space Model
  The value of the cosmological constant arising from a crystalline model for vacuum cosmic space with lattice parameter of the order of the neutron radius [1] has been calculated. The model allows to solve, in an easy way, the problem of the cosmological constant giving the right order of magnitude, which corresponds very well with the mean value of matter density in the universe. The obtained value is about 10 to the power of (-48) square Km. Diffraction experiments with non-thermal neutron beam in cosmic space are proposed to search for the possibility of crystalline structure of vacuum space and to measure the lattice parameter. 
J. A. Montemayor-Aldrete, J. R. Morones-Ibarra, A. Morales-Mori, A.   Mendoza-Allende, A. Montemayor-Varela, M. del Castillo...