Vincent Black Shadow "White Shadow" models to the same mechanical specifications as the Black Shadows but with an engine that was polished rather than enamelled. White Shadow engines had a prefix of "1A/". In 2007 the Vincent H·R·D Owners Club commissioned the VOC Spares Company Limited to build a replica Black Shadow from new parts. The goal of the project was to prove that all parts were in stock and available from the VOC Spares Company Limited. Having received glowing reviews from the motorcycle press in the UK, the machine was auctioned by Bonhams and eventually went on display at a museum in
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