On rotation distance between binary coupling trees and applications for 3nj-coefficients
نویسندگان
چکیده
منابع مشابه
On Rotation Distance between Binary Coupling Trees and Applications for 3nj-coeecients
Generalized recoupling coeecients or 3nj-coeecients for a Lie algebra (with su(2), the Lie algebra for the quantum theory of angular momentum, as generic example) can always be expressed as multiple sums over products of Racah coeecients (i.e. 6j-coeecients). In general there exist many such expressions; we say that such an expression is optimal if the number of Racah coeecients in such a produ...
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We develop combinatorial methods for computing the rotation distance between binary trees, i.e., equivalently, the flip distance between triangulations of a polygon. As an application, we prove that, for each n, there exist size n trees at distance 2n − O( √ n). If T, T ′ are finite binary rooted trees, one says that T ′ is obtained from T by one rotation if T ′ coincides with T except in the n...
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Tree rotations (left and right) are basic local deformations allowing to transform between two unlabeled binary trees of the same size. Hence, there is a natural problem of practically finding such transformation path with low number of rotations, the optimal minimal number is called the rotation distance. Such distance could be used for instance to quantify similarity between two trees for var...
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ژورنال
عنوان ژورنال: Computer Physics Communications
سال: 1999
ISSN: 0010-4655
DOI: 10.1016/s0010-4655(99)00216-7