The octogenarian American artist Larry Bell is renowned for his geometric glass sculptures, which resist classification. (Bell was already a cult figure in 1967, when he appeared on the cover of the Beatles’ album “Sgt. Pepper’s Lonely Hearts Club Band.”) Dia:Beacon, in the Hudson Valley, has opened a long-term installation of Bell’s works, both historic and new, including “Nesting Boxes” (pictured), from 2021, which he conceived specifically for the space it now occupies.