(Photo: Bernd Uhlig) Matthias Pintscher’s new opera, “Das kalte Herz” (The Cold Heart), with a libretto by Daniel Arkadij Gerzenberg, is not a retelling of German author Wilhelm Hauff’s famous fairy tale from 1827—that text written in the spirit of the Biedermeier period, which can be read as a subtle critique of early industrialization and unbridled capitalism—but rather its condensation {…}