  We elaborate on the new understanding of the cosmological constant and the
gauge hierarchy problems in the context of string theory in its metastring
formulation, based on the concepts of modular spacetime and Born geometry. The
interplay of phase space (and Born geometry), the Bekenstein bound, the mixing
between ultraviolet (UV) and infrared (IR) physics and modular invariance in
string theory is emphasized. This new viewpoint is fundamentally rooted in
quantum contextuality and not in statistical observer bias (anthropic
principle). We also discuss the extension of this point of view to the problem
of masses of quarks and leptons and their respective mixing matrices.
