It takes Stephen Hawking 15 minutes to convert four lines of written text into spoken words. So his 50-minute Albert Einstein Lecture 2001, 'Predicting The Future: From Astrology to Black Holes', at the Siri Fort Auditorium on Wednesday will be a real labour of love. The guru of cosmology lost his voice to pneumonia in 1984, but the voice synthesiser that has been his constant companion since then is "painstakingly slow and in desperate need to be updated," says his one-time doctoral student, Professor Daksh Lohia of Delhi University's Astrophysics and Cosmology Department.