文摘
Let FF denote a field, and let V denote a vector space over FF with finite positive dimension. Pick a nonzero q∈Fq∈F such that q4≠1q4≠1, and let A,B,CA,B,C denote a Leonard triple on V that has q -Racah type. We show that there exist invertible W,W′,W″W,W′,W″ in End(V)End(V) such that (i) A commutes with W and W−1BW−CW−1BW−C; (ii) B commutes with W′W′ and (W′)−1CW′−A(W′)−1CW′−A; (iii) C commutes with W″W″ and (W″)−1AW″−B(W″)−1AW″−B. Moreover each of W,W′,W″W,W′,W″ is unique up to multiplication by a nonzero scalar in FF. We show that the three elements W′W,W″W′,WW″W′W,W″W′,WW″ mutually commute, and their product is a scalar multiple of the identity. A number of related results are obtained. We call W,W′,W″W,W′,W″ the pseudo intertwiners for A,B,CA,B,C.