Elizabeth Fiedler talks with former Philadelphia Police Commissioner John Timoney about the public safety challenges older cities face. Maiken Scott looks at the effect of instant, graphic images from tragedies that flood social media and traditional journalism. Yowei Shaw reviews Philadelphia’s recent history of flash mobs and whether there’s more lying ahead for the city. Penn Religious Studies professor Justin McDaniel tells Dave Heller about the contemplative life his students tested for a month. Peter Crimmins meets up with jazz trumpeter Terence Blanchard, who’s in town to teach high school muaic students.