Type II Matrices and Their Bose-Mesner Algebras

نویسندگان

  • RIE HOSOYA
  • HIROSHI SUZUKI
چکیده

Type II matrices were introduced in connection with spin models for link invariants. It is known that a pair of Bose-Mesner algebras (called a dual pair) of commutative association schemes are naturally associated with each type II matrix. In this paper, we show that type II matrices whose Bose-Mesner algebras are imprimitive are expressed as so-called generalized tensor products of some type II matrices of smaller sizes. As an application, we give a classification of type II matrices of size at most 10 except 9 by using the classification of commutative association schemes.

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تاریخ انتشار 2003