generic derivation : delta:= mat((xi(1,1),0,0,0,0,0),(xi(2,1),xi(2,2),0,0,0,0),(xi(3,1),xi(3,2),xi(2,2) + xi( 1,1),0,0,0),(xi(4,1),xi(4,2),xi(3,2),xi(2,2) + 2*xi(1,1),xi(4,5),xi(4,6)),(xi(5, 1),xi(5,2),0,0,xi(5,5),xi(5,6)),(xi(6,1),xi(6,2),0,0,xi(6,5),xi(6,6)))$ [0 0 0 0 0 0] [ ] [0 0 0 0 0 0] [ ] [0 1 0 0 0 0] adx1 := [ ] [0 0 1 0 0 0] [ ] [0 0 0 0 0 0] [ ] [0 0 0 0 0 0] [0 0 0 0 0 0] [ ] [0 0 0 0 0 0] [ ] [-1 0 0 0 0 0] adx2 := [ ] [0 0 0 0 0 0] [ ] [0 0 0 0 0 0] [ ] [0 0 0 0 0 0] [0 0 0 0 0 0] [ ] [0 0 0 0 0 0] [ ] [0 0 0 0 0 0] adx3 := [ ] [-1 0 0 0 0 0] [ ] [0 0 0 0 0 0] [ ] [0 0 0 0 0 0] The generic nilpotent derivation : the eigenvalues are 0 xi(1,1):=0 xi(2,2):=0 And the matrix A:=(xi(5,5),xi(5,6)),(xi(6,5),xi(6,6)) is nilpotent We hence get 2 cases according to whether A neq 0 or A=0. We consider here the case 2 where A := 0. xi(5,5):=0 xi(5,6):=0 xi(6,5):=0 xi(6,6):=0 by subtracting adjoints one then may suppose: xi(3,1):=0,xi(3,2):=0,xi(4,1):=0 delta:= [ 0 0 0 0 0 0 ] [ ] [xi(2,1) 0 0 0 0 0 ] [ ] [ 0 0 0 0 0 0 ] [ ] [ 0 xi(4,2) 0 0 xi(4,5) xi(4,6)] [ ] [xi(5,1) xi(5,2) 0 0 0 0 ] [ ] [xi(6,1) xi(6,2) 0 0 0 0 ] We denote this delta by the shortform shortformdelta:={xi(2,1), ss, xi(4,2), xi(4,5), xi(4,6), ss, xi(5,1), xi(5,2), ss, xi(6,1), xi(6,2)} paramindexeslist:={{2,1},{4,2},{4,5},{4,6},{5,1},{5,2},{6,1},{6,2}} a:=1$ delta:= mat((0,0,0,0,0,0),(0,0,0,0,0,0),(0,0,0,0,0,0),(0,0,0,0,0,1),(0,1,0,0,0,0),(1,0,0 ,0,0,0))$ shortformdelta:={0,ss,0,0,1,ss,0,1,ss,1,0}$ on resout l'equation {{0,1},0} qui est maintenant AA:= - d(0,6)$ Unknown: d(0,6) Unknown: d(0,6) bonne inconnue W:=d(0,6)$ sa valeur doit etre WW:=0$ on resout l'equation {{0,1},1} qui est maintenant AA:= - d(1,6)$ Unknown: d(1,6) Unknown: d(1,6) bonne inconnue W:=d(1,6)$ sa valeur doit etre WW:=0$ on resout l'equation {{0,1},2} qui est maintenant AA:= - d(2,6)$ Unknown: d(2,6) Unknown: d(2,6) bonne inconnue W:=d(2,6)$ sa valeur doit etre WW:=0$ on resout l'equation {{0,1},3} qui est maintenant AA:= - (d(3,6) + d(2,0))$ Unknowns: {d(3,6),d(2,0)} Unknowns: {d(3,6),d(2,0)} bonne inconnue W:=d(3,6)$ sa valeur doit etre WW:= - d(2,0)$ on resout l'equation {{0,1},4} qui est maintenant AA:=d(6,1) - d(4,6) - d(3,0)$ Unknowns: {d(6,1),d(4,6),d(3,0)} Unknowns: {d(6,1),d(4,6),d(3,0)} bonne inconnue W:=d(6,1)$ sa valeur doit etre WW:=d(4,6) + d(3,0)$ on resout l'equation {{0,1},5} qui est maintenant AA:= - d(5,6) + d(2,1)$ Unknowns: {d(5,6),d(2,1)} Unknowns: {d(5,6),d(2,1)} bonne inconnue W:=d(5,6)$ sa valeur doit etre WW:=d(2,1)$ on resout l'equation {{0,1},6} qui est maintenant AA:= - d(6,6) + d(1,1) + d(0, 0)$ Unknowns: {d(6,6),d(1,1),d(0,0)} Unknowns: {d(6,6),d(1,1),d(0,0)} bonne inconnue W:=d(6,6)$ sa valeur doit etre WW:=d(1,1) + d(0,0)$ on resout l'equation {{0,2},0} qui est maintenant AA:= - d(0,5)$ Unknown: d(0,5) Unknown: d(0,5) bonne inconnue W:=d(0,5)$ sa valeur doit etre WW:=0$ on resout l'equation {{0,2},1} qui est maintenant AA:= - d(1,5)$ Unknown: d(1,5) Unknown: d(1,5) bonne inconnue W:=d(1,5)$ sa valeur doit etre WW:=0$ on resout l'equation {{0,2},2} qui est maintenant AA:= - d(2,5)$ Unknown: d(2,5) Unknown: d(2,5) bonne inconnue W:=d(2,5)$ sa valeur doit etre WW:=0$ on resout l'equation {{0,2},3} qui est maintenant AA:= - d(3,5) + d(1,0)$ Unknowns: {d(3,5),d(1,0)} Unknowns: {d(3,5),d(1,0)} bonne inconnue W:=d(3,5)$ sa valeur doit etre WW:=d(1,0)$ on resout l'equation {{0,2},4} qui est maintenant AA:=d(6,2) - d(4,5)$ Unknowns: {d(6,2),d(4,5)} Unknowns: {d(6,2),d(4,5)} bonne inconnue W:=d(6,2)$ sa valeur doit etre WW:=d(4,5)$ on resout l'equation {{0,2},5} qui est maintenant AA:= - d(5,5) + d(2,2) + d(0, 0)$ Unknowns: {d(5,5),d(2,2),d(0,0)} Unknowns: {d(5,5),d(2,2),d(0,0)} bonne inconnue W:=d(5,5)$ sa valeur doit etre WW:=d(2,2) + d(0,0)$ on resout l'equation {{0,2},6} qui est maintenant AA:= - d(6,5) + d(1,2)$ Unknowns: {d(6,5),d(1,2)} Unknowns: {d(6,5),d(1,2)} bonne inconnue W:=d(6,5)$ sa valeur doit etre WW:=d(1,2)$ on resout l'equation {{0,3},4} qui est maintenant AA:=d(6,3) + d(1,0)$ Unknowns: {d(6,3),d(1,0)} Unknowns: {d(6,3),d(1,0)} bonne inconnue W:=d(6,3)$ sa valeur doit etre WW:= - d(1,0)$ on resout l'equation {{0,3},5} qui est maintenant AA:=d(2,3)$ Unknown: d(2,3) Unknown: d(2,3) bonne inconnue W:=d(2,3)$ sa valeur doit etre WW:=0$ on resout l'equation {{0,3},6} qui est maintenant AA:=d(1,3)$ Unknown: d(1,3) Unknown: d(1,3) bonne inconnue W:=d(1,3)$ sa valeur doit etre WW:=0$ on resout l'equation {{0,4},4} qui est maintenant AA:=d(6,4)$ Unknown: d(6,4) Unknown: d(6,4) bonne inconnue W:=d(6,4)$ sa valeur doit etre WW:=0$ on resout l'equation {{0,4},5} qui est maintenant AA:=d(2,4)$ Unknown: d(2,4) Unknown: d(2,4) bonne inconnue W:=d(2,4)$ sa valeur doit etre WW:=0$ on resout l'equation {{0,4},6} qui est maintenant AA:=d(1,4)$ Unknown: d(1,4) Unknown: d(1,4) bonne inconnue W:=d(1,4)$ sa valeur doit etre WW:=0$ on resout l'equation {{0,5},4} qui est maintenant AA:=d(1,2)$ Unknown: d(1,2) Unknown: d(1,2) bonne inconnue W:=d(1,2)$ sa valeur doit etre WW:=0$ on resout l'equation {{0,6},0} qui est maintenant AA:= - d(0,4)$ Unknown: d(0,4) Unknown: d(0,4) bonne inconnue W:=d(0,4)$ sa valeur doit etre WW:=0$ on resout l'equation {{0,6},3} qui est maintenant AA:= - d(3,4)$ Unknown: d(3,4) Unknown: d(3,4) bonne inconnue W:=d(3,4)$ sa valeur doit etre WW:=0$ on resout l'equation {{0,6},4} qui est maintenant AA:= - d(4,4) + d(1,1) + 2*d( 0,0)$ Unknowns: {d(4,4),d(1,1),d(0,0)} Unknowns: {d(4,4),d(1,1),d(0,0)} bonne inconnue W:=d(4,4)$ sa valeur doit etre WW:=d(1,1) + 2*d(0,0)$ on resout l'equation {{0,6},5} qui est maintenant AA:= - d(5,4)$ Unknown: d(5,4) Unknown: d(5,4) bonne inconnue W:=d(5,4)$ sa valeur doit etre WW:=0$ on resout l'equation {{1,2},0} qui est maintenant AA:= - d(0,3)$ Unknown: d(0,3) Unknown: d(0,3) bonne inconnue W:=d(0,3)$ sa valeur doit etre WW:=0$ on resout l'equation {{1,2},3} qui est maintenant AA:= - d(3,3) + d(2,2) + d(1, 1)$ Unknowns: {d(3,3),d(2,2),d(1,1)} Unknowns: {d(3,3),d(2,2),d(1,1)} bonne inconnue W:=d(3,3)$ sa valeur doit etre WW:=d(2,2) + d(1,1)$ on resout l'equation {{1,2},4} qui est maintenant AA:= - d(4,3) + d(3,2)$ Unknowns: {d(4,3),d(3,2)} Unknowns: {d(4,3),d(3,2)} bonne inconnue W:=d(4,3)$ sa valeur doit etre WW:=d(3,2)$ on resout l'equation {{1,2},5} qui est maintenant AA:= - d(5,3) + d(0,1)$ Unknowns: {d(5,3),d(0,1)} Unknowns: {d(5,3),d(0,1)} bonne inconnue W:=d(5,3)$ sa valeur doit etre WW:=d(0,1)$ on resout l'equation {{1,2},6} qui est maintenant AA:=d(1,0) - d(0,2)$ Unknowns: {d(1,0),d(0,2)} Unknowns: {d(1,0),d(0,2)} bonne inconnue W:=d(1,0)$ sa valeur doit etre WW:=d(0,2)$ on resout l'equation {{1,3},4} qui est maintenant AA:=d(2,2) + d(1,1) - 2*d(0,0 )$ Unknowns: {d(2,2),d(1,1),d(0,0)} Unknowns: {d(2,2),d(1,1),d(0,0)} bonne inconnue W:=d(2,2)$ sa valeur doit etre WW:= - d(1,1) + 2*d(0,0)$ on resout l'equation {{1,5},4} qui est maintenant AA:=d(0,2)$ Unknown: d(0,2) Unknown: d(0,2) bonne inconnue W:=d(0,2)$ sa valeur doit etre WW:=0$ on resout l'equation {{1,6},4} qui est maintenant AA:= - d(2,0) + d(0,1)$ Unknowns: {d(2,0),d(0,1)} Unknowns: {d(2,0),d(0,1)} bonne inconnue W:=d(0,1)$ sa valeur doit etre WW:=d(2,0)$ Derivation equations to cancel (Reduce output) : \\{{{{0,1},0},0}, {{{0,1},1},0}, {{{0,1},2},0}, {{{0,1},3},0}, {{{0,1},4},0}, {{{0,1},5},0}, {{{0,1},6},0}, {{{0,2},0},0}, {{{0,2},1},0}, {{{0,2},2},0}, {{{0,2},3},0}, {{{0,2},4},0}, {{{0,2},5},0}, {{{0,2},6},0}, {{{0,3},4},0}, {{{0,3},5},0}, {{{0,3},6},0}, {{{0,4},4},0}, {{{0,4},5},0}, {{{0,4},6},0}, {{{0,5},4},0}, {{{0,5},5},0}, {{{0,5},6},0}, {{{0,6},0},0}, {{{0,6},1},0}, {{{0,6},2},0}, {{{0,6},3},0}, {{{0,6},4},0}, {{{0,6},5},0}, {{{0,6},6},0}, {{{1,2},0},0}, {{{1,2},1},0}, {{{1,2},2},0}, {{{1,2},3},0}, {{{1,2},4},0}, {{{1,2},5},0}, {{{1,2},6},0}, {{{1,3},0},0}, {{{1,3},1},0}, {{{1,3},2},0}, {{{1,3},3},0}, {{{1,3},4},0}, {{{1,3},5},0}, {{{1,3},6},0}, {{{1,4},3},0}, {{{1,4},4},0}, {{{1,4},6},0}, {{{1,5},3},0}, {{{1,5},4},0}, {{{1,5},6},0}, {{{1,6},3},0}, {{{1,6},4},0}, {{{1,6},6},0}, {{{2,3},3},0}, {{{2,3},4},0}, {{{2,3},5},0}, {{{2,4},3},0}, {{{2,4},5},0}, {{{2,5},3},0}, {{{2,5},5},0}, {{{2,6},3},0}, {{{2,6},4},0}, {{{2,6},5},0}, {{{3,4},4},0}, {{{3,5},4},0}, {{{3,6},4},0}, {{{4,6},4},0}, {{{5,6},4},0}}$ Il n'y a pas de phase 2$ derivation generique de gtildedelta:$ MATD:= mat((d(0,0),d(2,0),0,0,0,0,0),(0,d(1,1),0,0,0,0,0),(d(2,0),d(2,1), - d(1,1) + 2* d(0,0),0,0,0,0),(d(3,0),d(3,1),d(3,2),2*d(0,0),0,0, - d(2,0)),(d(4,0),d(4,1),d(4 ,2),d(3,2),d(1,1) + 2*d(0,0),d(4,5),d(4,6)),(d(5,0),d(5,1),d(5,2),d(2,0),0, - d( 1,1) + 3*d(0,0),d(2,1)),(d(6,0),d(4,6) + d(3,0),d(4,5),0,0,0,d(1,1) + d(0,0)))$ pour delta:= [0 0 0 0 0 0] [ ] [0 0 0 0 0 0] [ ] [0 0 0 0 0 0] [ ] [0 0 0 0 0 1] [ ] [0 1 0 0 0 0] [ ] [1 0 0 0 0 0] pour shortformdelta:={0,ss,0,0,1,ss,0,1,ss,1,0} Unknowns: {d(6,0), d(5,2), d(5,1), d(5,0), d(4,6), d(4,5), d(4,2), d(4,1), d(4,0), d(3,2), d(3,1), d(3,0), d(2,1), d(2,0), d(1,1), d(0,0)} Unknowns: {d(6,0), d(5,2), d(5,1), d(5,0), d(4,6), d(4,5), d(4,2), d(4,1), d(4,0), d(3,2), d(3,1), d(3,0), d(2,1), d(2,0), d(1,1), d(0,0)} listeparametresMATD{d(6,0), d(5,2), d(5,1), d(5,0), d(4,6), d(4,5), d(4,2), d(4,1), d(4,0), d(3,2), d(3,1), d(3,0), d(2,1), d(2,0), d(1,1), d(0,0)}$ dim Der(gtildedelta):=16$ t1:=D(0,0):= [1 0 0 0 0 0 0] [ ] [0 0 0 0 0 0 0] [ ] [0 0 2 0 0 0 0] [ ] [0 0 0 2 0 0 0] [ ] [0 0 0 0 2 0 0] [ ] [0 0 0 0 0 3 0] [ ] [0 0 0 0 0 0 1] Unknowns: {d(6,0),d(4,2),d(3,2),d(1,1),d(0,0)} Unknowns: {d(6,0),d(4,2),d(3,2),d(1,1),d(0,0)} t2:=D(1,1):= [0 0 0 0 0 0 0] [ ] [0 1 0 0 0 0 0] [ ] [0 0 -1 0 0 0 0] [ ] [0 0 0 0 0 0 0] [ ] [0 0 0 0 1 0 0] [ ] [0 0 0 0 0 -1 0] [ ] [0 0 0 0 0 0 1] Unknowns: {d(1,1),d(0,0)} Unknowns: {d(1,1),d(0,0)} commutant simultane de t1,t2 dans der(gtildedelta):$ mat((d(0,0),0,0,0,0,0,0),(0,d(1,1),0,0,0,0,0),(0,0, - d(1,1) + 2*d(0,0),0,0,0,0) ,(0,0,0,2*d(0,0),0,0,0),(0,0,0,0,d(1,1) + 2*d(0,0),0,0),(0,0,0,0,0, - d(1,1) + 3 *d(0,0),0),(0,0,0,0,0,0,d(1,1) + d(0,0)))$ rank 2 with maximal torus t1,t2 2 matrice de passage de la base X(0)=delta, X(1),..., X(6) a une base diagonali\ sant le tore maximal: on peut prendre P:= [1 0 0 0 0 0 0] [ ] [0 1 0 0 0 0 0] [ ] [0 0 1 0 0 0 0] [ ] [0 0 0 1 0 0 0] [ ] [0 0 0 0 1 0 0] [ ] [0 0 0 0 0 1 0] [ ] [0 0 0 0 0 0 1] P**(-1)*t1*P:= [1 0 0 0 0 0 0] [ ] [0 0 0 0 0 0 0] [ ] [0 0 2 0 0 0 0] [ ] [0 0 0 2 0 0 0] [ ] [0 0 0 0 2 0 0] [ ] [0 0 0 0 0 3 0] [ ] [0 0 0 0 0 0 1] P**(-1)*t2*P:= [0 0 0 0 0 0 0] [ ] [0 1 0 0 0 0 0] [ ] [0 0 -1 0 0 0 0] [ ] [0 0 0 0 0 0 0] [ ] [0 0 0 0 1 0 0] [ ] [0 0 0 0 0 -1 0] [ ] [0 0 0 0 0 0 1] matrice des derivations dans cette base diagonalisante Y(1),...,Y(7): P**(-1)*MATD*P:= mat((d(0,0),d(2,0),0,0,0,0,0),(0,d(1,1),0,0,0,0,0),(d(2,0),d(2,1), - d(1,1) + 2* d(0,0),0,0,0,0),(d(3,0),d(3,1),d(3,2),2*d(0,0),0,0, - d(2,0)),(d(4,0),d(4,1),d(4 ,2),d(3,2),d(1,1) + 2*d(0,0),d(4,5),d(4,6)),(d(5,0),d(5,1),d(5,2),d(2,0),0, - d( 1,1) + 3*d(0,0),d(2,1)),(d(6,0),d(4,6) + d(3,0),d(4,5),0,0,0,d(1,1) + d(0,0)))$ PP:= [1 0 0 0 0 0 0] [ ] [0 1 0 0 0 0 0] [ ] [0 0 1 0 0 0 0] [ ] [0 0 0 1 0 0 0] [ ] [0 0 0 0 1 0 0] [ ] [0 0 0 0 0 1 0] [ ] [0 0 0 0 0 0 1] avec PP:=P*Q:= [1 0 0 0 0 0 0] [ ] [0 1 0 0 0 0 0] [ ] [0 0 1 0 0 0 0] [ ] [0 0 0 1 0 0 0] [ ] [0 0 0 0 1 0 0] [ ] [0 0 0 0 0 1 0] [ ] [0 0 0 0 0 0 1] MATDDIAGONALISE:= mat((d(0,0),d(2,0),0,0,0,0,0), (0,d(1,1),0,0,0,0,0), (d(2,0),d(2,1), - d(1,1) + 2*d(0,0),0,0,0,0), (d(3,0),d(3,1),d(3,2),2*d(0,0),0,0, - d(2,0)), (d(4,0),d(4,1),d(4,2),d(3,2),d(1,1) + 2*d(0,0),d(4,5),d(4,6)), (d(5,0),d(5,1),d(5,2),d(2,0),0, - d(1,1) + 3*d(0,0),d(2,1)), (d(6,0),d(4,6) + d(3,0),d(4,5),0,0,0,d(1,1) + d(0,0))) on voit apparaitre les poids sur la diagonale r(1) := d(0,0) r(2) := d(1,1) r(3) := - d(1,1) + 2*d(0,0) r(4) := 2*d(0,0) r(5) := d(1,1) + 2*d(0,0) r(6) := - d(1,1) + 3*d(0,0) r(7) := d(1,1) + d(0,0) r(1) := gamma2 r(2) := gamma1 r(3) := - (gamma1 - 2*gamma2) r(4) := 2*gamma2 r(5) := gamma1 + 2*gamma2 r(6) := - (gamma1 - 3*gamma2) r(7) := gamma1 + gamma2 Le systeme de poids est le systeme 2.44 calcul de relations de commutation de la base diaY(j) diagonalisant le tore listcommutateursdesx := {{{0,1},x(6)}, {{0,2},x(5)}, {{0,3},0}, {{0,4},0}, {{0,5},0}, {{0,6},x(4)}, {{1,2},x(3)}, {{1,3},x(4)}, {{1,4},0}, {{1,5},0}, {{1,6},0}, {{2,3},0}, {{2,4},0}, {{2,5},0}, {{2,6},0}, {{3,4},0}, {{3,5},0}, {{3,6},0}, {{4,5},0}, {{4,6},0}, {{5,6},0}} diaY(1):=x(0) diaY(2):=x(1) diaY(3):=x(2) diaY(4):=x(3) diaY(5):=x(4) diaY(6):=x(5) diaY(7):=x(6) liste des commutateurs des diaY(i) :$ listcommutateurdesdiaY:={{{1,2},diay(7)}, {{1,3},diay(6)}, {{1,4},0}, {{1,5},0}, {{1,6},0}, {{1,7},diay(5)}, {{2,3},diay(4)}, {{2,4},diay(5)}, {{2,5},0}, {{2,6},0}, {{2,7},0}, {{3,4},0}, {{3,5},0}, {{3,6},0}, {{3,7},0}, {{4,5},0}, {{4,6},0}, {{4,7},0}, {{5,6},0}, {{5,7},0}, {{6,7},0}}$ Now we make explicit the isomorphism with an algebra of the book:$ Namely g_{7,2.44}$ i.e. we go from the basis diaY(i) to the new basis ZZ(i) defined by the matrix:$ on pose :$ avec comme matrice de changement de base :$ mat((0,-1,0,0,0,0,0),(1,0,0,0,0,0,0),(0,0,-1,0,0,0,0),(0,0,0,0,-1,0,0),(0,0,0,0, 0,0,-1),(0,0,0,0,0,1,0),(0,0,0,1,0,0,0))$ det(isom):= -1$ ZZ(1):=diay(2)$ ZZ(2):= - diay(1)$ ZZ(3):= - diay(3)$ ZZ(4):=diay(7)$ ZZ(5):= - diay(4)$ ZZ(6):=diay(6)$ ZZ(7):= - diay(5)$ listcommutateursdesZZ:=$ {{1,2},zz(4)}$ {{1,3},zz(5)}$ {{1,4},0}$ {{1,5},zz(7)}$ {{1,6},0}$ {{1,7},0}$ {{2,3},zz(6)}$ {{2,4},zz(7)}$ {{2,5},0}$ {{2,6},0}$ {{2,7},0}$ {{3,4},0}$ {{3,5},0}$ {{3,6},0}$ {{3,7},0}$ {{4,5},0}$ {{4,6},0}$ {{4,7},0}$ {{5,6},0}$ {{5,7},0}$ {{6,7},0}$ We get the commutation relations of$ g_{7,2.44}$ Et cela pour a:=1$ shortformdelta:={0,ss,0,0,1,ss,0,1,ss,1,0}$ delta:= mat((0,0,0,0,0,0),(0,0,0,0,0,0),(0,0,0,0,0,0),(0,0,0,0,0,1),(0,1,0,0,0,0),(1,0,0 ,0,0,0))$