Sir Tom Stoppard (he was knighted in 1997) might be our greatest living playwright. He’s still cranking out plays at the age of 75, but his acknowledged masterpiece is probably Arcadia, which is being staged by the drama program at UC’s College-Conservatory of Music this weekend. The witty play from 1993 veers back and forth between interconnected events in the early 19th century and the present in the same country house in rural England. Two modern scholars in the present spar and speculate about events that happened in 1809. It’s a fascinating and complicated exploration of the relationships between past and present, knowledge and passion, science and poetry. Drama professor Diane Kvapil directs a student cast who play poets, scholars, nobility, servants and a very precocious teenage girl and her tutor. Through Sunday.