The U.S. needs find a way to be a leader in global peace, former President Jimmy Carter said Monday at a gathering of Nobel Peace Prize winners. Mikhail Gorbachev and the Dalai Lama are just a few laureates expected in Chicago for the three-day summit, the first of its kind in North America. The World Summit of Nobel Peace Laureates comes just weeks before Chicago hosts President Barack Obama and numerous foreign leaders for the NATO summit. They were scheduled Monday to attend a dinner with former President Bill Clinton.Other Nobel Prize winners expected to attend include former Polish President Lech Walesa and professor Muhammad Yunus of Bangladesh. Actor Sean Penn will be presented with the 2012 Peace Summit Award for his work in Haiti. The Nobel summit — titled “Speak Up, Speak Out for Freedom and Rights” — runs through Wednesday. … George Harrison was recording steadily at the studio in his English country estate until nearly the day he died in 2001, according to his widow, Olivia Harrison. “He was just getting to the point of getting some sessions together. Sadly, time ran out.” Now, Olivia Harrison and a few trusted collaborators, including Giles Martin, the son of Beatles producer George Martin, are going through the guitarist’s massive archive and bringing the best of it to the public. The first in what is projected to be a series of recordings is due out May 1, “Early Takes: Volume 1” (UMe), a collection of mostly acoustic demos documenting the early days of Harrison’s solo career. It will accompany the release on DVD and Blu-Ray of Martin Scorsese’s 2011 Harrison documentary, “Living in the Material World.” “Early Takes” focuses on the era around the guitarist’s 1970 solo debut, “All Things Must Pass,” including demos or early takes of the title song, “My Sweet Lord,” “Behind That Locked Door,” “Awaiting On You All,” “Run of the Mill” and “I’d Have You Any Time” (co-written with Bob Dylan). Another gem is an acoustic version of the then-decade-old Everly Brothers hit “Let It Be Me.”