Shortly after the premiere of “Salesman” on Broadway, a translation was made by the actor Joseph Buloff, who performed it with his wife, Luba Kadison, first in Argentina and then, with Miller’s blessing, at the Parkway Theatre in Brooklyn. If Willy Loman was Jewish, did he speak Yiddish? The obvious answer, considering that the play was written and performed in English, is no. Now a new production of “Death of a Salesman” asks a further question. If Willy once had Jewish roots, they are long gone. Yet there is no sign in the script that the Lomans are Jews. He even based the play on his own uncle, a boastful salesman who struggled to make a living. Loman’s precarious life was the fate of many Jews in the 20th century, and playwright Arthur Miller - whose centenary is being celebrated this month - was the son and grandson of Jewish immigrants. Is “Death of a Salesman” a Jewish play? Is Willy Loman, its main character, Jewish? The question has been asked almost since “Salesman” was first produced, in 1949.