Vincent Black Prince Vincent Black Prince The Vincent Black Prince was a British motorcycle made between 1954 and 1955 by Vincent Motorcycles. A year before the factory closed in 1955, Vincent produced the enclosed range of Vincent Black Knight and Black Prince. Philip Vincent described it as a "two-wheeled Bentley", and the enclosed Vincents attracted a lot of attention at the November 1954 Earls Court show. Quality problems with early production of the glass-fibre mouldings necessitated a replacement supplier causing delays. The last Black Prince left the Vincent production line on Friday, 16 December 1955. Falling sales of the Series C Vincent motorcycles
Nonsingular black hole models Nonsingular black hole models A nonsingular black hole model is a mathematical theory of black holes that avoids certain theoretical problems with the standard black hole model, including information loss and the unobservable nature of the black hole event horizon. For a black hole to physically exist as a solution to Einstein's equation, it must form an event horizon in finite time relative to outside observers. This requires an accurate theory of black hole formation, of which several have been proposed. In 2007, Shuan Nan Zhang of Tsinghua University proposed a model in which the event horizon of a potential