Quadruple jump controversy for the quadruple jump and penalizing skaters if it is not done successfully. In 2008, the scoring system adopted a requirement that a failed quad receive a deduction of up to three points. This has led to some skaters feeling that attempting to do a quad is not worth the risk and reward, as much easier jumps present a better opportunity for athletes to collect the needed points. "I had one fall in my program on a triple lutz. They considered it a double with a fall. I got 1.09 points. Then Nobunari Oda fell on a quad but they
Quadruple product Quadruple product In mathematics, the quadruple product is a product of four vectors in three-dimensional Euclidean space. The name "quadruple product" is used for two different products, the scalar-valued scalar quadruple product and the vector-valued vector quadruple product or vector product of four vectors . The scalar quadruple product is defined as the dot product of two cross products: where a, b, c, d are vectors in three-dimensional Euclidean space. It can be evaluated using the identity: or using the determinant: The vector quadruple product is defined as the cross product of two cross products: where a, b, c, d