Cosmological strings and gravitational lens effects

In the framework of the grand unification models, the necessary condition for the existence of cosmological strings is physically grounded in the presence of mirror doubles of ordinary particles and fields. These strings - Alice's strings - in addition to the effects of gravitational lens and of perturbations of matter and radiation caused by their large linear density change the relative mirror property of astronomical objects and of their radiation| this can lead to rapid luminosity variations of quasar and to differences between the spectra of lens images of a quasar| due to the symmetry of the average characteristics of the ordinary and mirror radiation of galaxies, the difference of the images of remote galaxies can be caused only by the asymmetri of their location with respect to the string line of sight