Earlier this fall, Chris Thile won a coveted MacArthur Genius Grant - $500,000 over the next five years, no strings attached. Why? Because Thile, who cut his teeth in the bluegrass group Nickel Creek, is arguably the best mandolin player on planet Earth. He now leads the Punch Brothers, a virtuosic folk-bluegrass outfit that employs the primary instruments of the genre - acoustic guitar, banjo, fiddle, upright bass and mandolin - but draws outside the lines in terms of melody and song structure. (Its latest, Who's Feeling Young Now?
, includes an unironic and pretty great cover of Radiohead's "Kid A.") If you're into bluegrass music, there's really no excuse not to be listening to these guys or not seeing them tonight, Tuesday, December 11, at the Beaumont Club. With the Milk Carton Kids. 7 p.m.