I hope he will speak to him. among others. of an innocent man who is now in danger of being sentenced to hard labor in the Soviet Union. His name is Leonid Volvovaky. a 45yearold mathematician. his trial opened Friday in Gorky. His "crime". active involvement with the large "refusenik" community there. His friends are worried that the prosecution may use his case as a warning. handing down a severe condemnation. Leonid is married to Ludmila. they have a 17yearold daughter. Kira. Their troubles began in 1976 when they applied for an exit visa to Israel. In the eyes of officialdom. Leonid became an outcast.