At first blush Arve Henriksen and Nils Petter Molvaer might seem nearly indistinguishable. Both are pristine-sounding Norwegian trumpeters with conspicuous investment in electronics. They share a fondness for fragile lyricism and rippling atmosphere, building on a 40-year tradition that began with the Miles Davis album “In a Silent Way.” Both have pushed toward modern fusions, imbuing chamberlike or folkloric pop music with currents of improvisation…..