A group of scientists from the University of California at Irvine (USA) has presented a comprehensive solution to one of the most controversial mysteries of Leonardo da Vinci. It reads like this "Why does the glass ball in the hand of Jesus from the painting" Salvatore Mundi "not refract light and create other optical effects?" The key is that this is not a ball, but a hollow thin-walled sphere.
This painting, at a price of $ 450 million, is considered one of the most expensive in the world - and also the most mysterious. For example, it is not completely known whether da Vinci had a hand in it at all - many researchers are inclined to think that the great scientist only completed a few strokes. In particular, the same ball, as a demonstration of the new (at that time) optical properties discovered by him. A kind of artifact, a scientific monument for the edification of descendants.
Solid glass ball (left) and hollow sphere (right)
Analysis of the shadows in the painting indicates the presence of a powerful light source from above, plus general ambient light. Right behind the ball are the folds of the cloak, which are not distorted in any way, which is impossible. American scientists using reverse rendering technology modeled this situation and calculated the parameters of the sphere: radius 6.8 cm, distance from the cloak 25 cm, glass thickness 1.3 mm. They carried out 3D modeling and were able to obtain indicators that are identical to what is shown in the picture.
The very idea of a hollow sphere has been put forward for a long time, but there were doubts - was it possible to create such a thing in 1500? A study of Americans, who took into account the level of development of technology at the time, showed that it is possible. But at the limit of possibilities, therefore, it is possible that da Vinci, who was then just carried away by optics, made a sphere, but could not continue to work. And he immortalized his achievement in the picture, adding to it an "impossible", a unique artifact with accurately conveyed physical properties.