For more than a year, Berkeley pianist and radio personality Sarah Cahill has been commissioning new works for piano on the theme of peace. Her impetus was frustration with the Iraq war, and a desire for music that would endure and resonate with audiences long after the war finally ends. (A similar frustration led David Harrington to found the Kronos Quartet with the goal of playing Crumb's Black Angels.) The fruits of her endeavors, a program entitled "A Sweeter Music," debuts this weekend at Cal Performances. Accompanied by a video installation by Emmy Award-winning video artist John Sanborn, Cahill will play eleven works by such well-known composers as Terry Riley, Frederic Rzewski, Yoko Ono, Larry Polansky, Jerome Kitzke, Pauline Oliveros, the Residents, Mamoru Fujieda, Carl Stone, and Peter Garland. (Don't miss the free roundtable discussion titled "Music of Peace: Can Music Be Political?" on Friday, Jan. 23 at 6 p.m. in Wheeler Auditorium). At Hertz Hall (Bancroft Way and Telegraph Ave, UC Berkeley) on Sunday, Jan. 25. 3 p.m., $38. CalPerformances.org or 510-642-9988.