No passport needed: Canada to California, Paris to Provincetown . . . Michael Cunningham and Adam Gopnik are the tour guides. 20 Summers at the Hawthorne Barn in Provincetown brought these two authors, a Pulitzer prize–winning novelist and a New Yorker writer, together on stage for the first time. WCAI's Sean Corcoran and Brian Morris sat in on a discussion that spanned the gamut from newsworthy to intimate, lofty to lowbrow, factual to imaginary- no topic was off limits.