  Weyl's original scale geometry of 1918 ("purely infinitesimal geometry") was
withdrawn from physical theory in the early 1920s. It had a comeback in the
last third of the 20th century in different contexts: scalar tensor theories of
gravity, foundations of physics (gravity, quantum mechanics), elementary
particle physics, and cosmology. Here we survey the last two segments. It seems
that Weyl geometry continues to have an open research potential for the
foundations of physics after the turn of the century.
