run "date"; needsPackage("LieAlgebraRepresentations"); sl6 = simpleLieAlgebra("A",5); rhoStd = standardRepresentation(sl6); rhoW2Std = exteriorPower(2,rhoStd); rhoW2Stdstar = dual rhoW2Std; -- Step 2: Get V02002 in W8W2Stdstar V02002 = irreducibleLieAlgebraModule({0,2,0,0,2},sl6); LAB = rhoStd#"Basis"; time L02002 = GTrepresentationMatrices(V02002); rhoV02002 = lieAlgebraRepresentation(V02002,LAB,L02002); -- Need a hwv for V02002 in W8W2Stdstar -- Relatively easy because the weight {0,2,0,0,2} subspace in W8W2Stdstar is one-dimensional wts = representationWeights(rhoW2Stdstar); s8 = subsets(apply(#wts, i -> i),8); t = first select(s8, s -> sum apply(s, j -> wts_j)=={0,2,0,0,2}) hwv = transpose matrix {apply(s8, s -> if s==t then 1/1 else 0/1)}; VInWedgekW(rhoV02002,8,rhoW2Stdstar,hwv,"SaveAsFunction"=>"V02002inW8W2Stdstar"); -- Step 3: Get V02000 in Sym2 V02002 V02000 = irreducibleLieAlgebraModule({0,2,0,0,0},sl6); L02000 = GTrepresentationMatrices(V02000); rhoV02000 = lieAlgebraRepresentation(V02000,LAB,L02000); hwv2 = weightMuHighestWeightVectorsInSymdW({0,2,0,0,0},2,rhoV02002); VInSymdW(rhoV02000,2,rhoV02002,hwv2_0,"SaveAsFunction"=>"V02000inS2V02002"); -- Step 4: Get the invariant in Sym3 V02000 hwv3 = weightMuHighestWeightVectorsInSymdW({0,0,0,0,0},3,rhoV02000); rhoV00000=trivialRepresentation(sl6); rhoV00000 = lieAlgebraRepresentation(rhoV00000#"Module",rhoV02000#"Basis",rhoV00000#"RepresentationMatrices"); V00000inS3V02000=VInSymdW(rhoV00000,3,rhoV02000,hwv3_0,"SaveAsFunction"=>"V00000inS3V02000"); run "date";