If you hadn’t guessed from his name, Gagan Singh is Sikh. And as you may know from Bollywood, the Sikh alpha male is a widely parodied stereotype in India, not least among Sikhs themselves. More than a few of the works (all Untitled) in Singh’s debut solo show, “Line Bombs,” exploit this familiar joke. Most numerous were a series of diminutive pen drawings from 2014, somewhere between David Shrigley and Dilbert, that depict a bigheaded, turbaned Singh boasting about things that are hardly worth mentioning—his love of butter chicken, his dumpy Maruti car, the greatness of his upstanding