 The ovoid profile of the dome has been the subject of much speculation and scholarship over the past century.Michelangelo died in 1564, leaving the drum of the dome complete, and Bramante's piers much bulkier than originally designed, each across.Following his death, the work continued under his assistant Jacopo Barozzi da Vignola with Giorgio Vasari appointed by Pope Pius V as a watchdog to make sure that Michelangelo's plans were carried out exactly.