R:= RootSystem( "A",7); U:=QuantizedUEA(R); g:= GeneratorsOfAlgebra( U ); PositiveRoots(R); PositiveRootsInConvexOrder(R); ########## generators of U ############### f1:=g[1]; f2:=g[3]; f3:=g[6]; f4:=g[10]; f5:=g[15]; f6:=g[21]; f7:=g[28]; e1:=g[43]; e2:=g[45]; e3:=g[48]; e4:=g[52]; e5:=g[57]; e6:=g[63]; e7:= g[70]; k1:=g[29]; k2:=g[31]; k3:=g[33]; k4:=g[35]; k5:=g[37]; k6:=g[39]; k7:=g[41]; k1m:=g[30]; k2m:=g[32]; k3m:=g[34]; k4m:=g[36]; k5m:=g[38]; k6m:=g[40]; k7m:=g[42]; ########## generators of B ############### b1:=f1 - k1m * e7; b2:=f2 - k2m * e6; b3:=f3 - k3m * e5; b4:=f4 - k4m * e4; b5:=f5 - k5m * e3; b6:=f6 - k6m * e2; b7:=f7 - k7m * e1; a1:= k1 * k7m; a2:= k2 * k6m; a3:= k3 * k5m; a5:= k5 * k3m; a6:= k6 * k2m; a7:= k7 * k1m; ########## q-numbers #################### 2q:=_q+_q^-1; ########## q-commutator ################# qcom2:=function(a,b) return a*b-_q*b*a; end; ######### relations in B as a function ######### rel1:=function(a,b) return a^2*b - (_q + _q^-1)*a*b*a + b*a^2 ; end; ################# relations #################### (_q-_q^-1)*(b1 * b7 - b7 * b1) - a1 + a7; (_q-_q^-1)*(b2 * b6 - b6 * b2) - a2 + a6; (_q-_q^-1)*(b3 * b5 - b5 * b3) - a3 + a5; rel1(b1,b2); rel1(b2,b1); b1 *b3 - b3* b1; b2 * b4 - b4 * b2; rel1(b2,b3); rel1(b3,b2); rel1(b3,b4); rel1(b5,b4); rel1(b4,b3) + _q^-1 * b3; rel1(b4,b5) + _q^-1 * b5; #### from here onwards it's symmetric rel1(b5,b6); rel1(b6,b5); ################# \tau_4^{-1} Braid group action ##################### t4mb1:=b1;; t4mb2:=b2;; t4mb3:=qcom2(b4,b3);; t4mb4:=b4;; t4mb5:=qcom2(b4,b5);; t4mb6:=b6;; t4mb7:=b7;; t4ma1:=a1;; t4ma2:=a2;; t4ma3:=a3;; t4ma5:=a5;; t4ma6:=a6;; t4ma7:=a7;; ################# t4m is an algebra homomorphism ############ (_q-_q^-1)*(t4mb3 * t4mb5 - t4mb5 * t4mb3) - t4ma3 + t4ma5; rel1(t4mb2,t4mb3); rel1(t4mb3,t4mb2); rel1(t4mb3, t4mb4); rel1(t4mb5, t4mb4); rel1(t4mb4, t4mb3) + _q^-1 * t4mb3; rel1(t4mb4, t4mb5) + _q^-1 * t4mb5; rel1(t4mb5,t4mb6); rel1(t4mb6,t4mb5); ################# the inverse \tau_4 of \tau_4^{-1} ################## t4b1:=b1;; t4b2:=b2;; t4b3:=qcom2(b3,b4);; t4b4:=b4;; t4b5:=qcom2(b5,b4);; t4b6:=b6;; t4b7:=b7;; t4a1:=a1;; t4a2:=a2;; t4a3:=a3;; t4a5:=a5;; t4a6:=a6;; t4a7:=a7;; ################ t4 is an algebra homomorphism ################ (_q-_q^-1)*(t4b3 * t4b5 - t4b5 * t4b3) - t4a3 + t4a5; rel1(t4b2,t4b3); rel1(t4b3,t4b2); rel1(t4b3,t4b4); rel1(t4b5,t4b4); rel1(t4b4,t4b3) + _q^-1 * t4b3; rel1(t4b4,t4b5) + _q^-1 * t4b5; rel1(t4b5,t4b6); rel1(t4b6,t4b5); ########### t4 is the inverse of t4m #################### qcom2(t4mb3,t4mb4)-b3; qcom2(t4mb5,t4mb4)-b5; ############ \tau_3^- braid group action #################### t3mb1:=b1;; t3mb2:= qcom2(b3,b2);; #### times q^(-1/2) t3mb3:= _q^-1 * a3* b5;; t3mb4:= _q^-1 * qcom2(b3,qcom2(b5,b4))+b4*a3;; t3mb5:= _q^-1 * a5 * b3;; t3mb6:= qcom2(b5,b6);; #### times _q^(-1/2) t3mb7:= b7;; t3ma1:= a1;; t3ma2:= a2*a3;; t3ma3:= a5;; t3ma5:= a3;; t3ma6:= a6*a5;; t3ma7:= a7;; ############ t3m is an algebra homomorphism ############# (_q-_q^-1)*(t3mb1 * t3mb7 - t3mb7 * t3mb1) - t3ma1 + t3ma7; (_q-_q^-1)* _q^-1* (t3mb2 * t3mb6 - t3mb6 * t3mb2) - t3ma2 + t3ma6; (_q-_q^-1)*(t3mb3 * t3mb5 - t3mb5 * t3mb3) - t3ma3 + t3ma5; rel1(t3mb1,t3mb2); rel1(t3mb2,t3mb1); t3mb1 * t3mb3 - t3mb3 * t3mb1; t3mb2 * t3mb4 - t3mb4 * t3mb2; rel1(t3mb2,t3mb3); rel1(t3mb3,t3mb2); rel1(t3mb3,t3mb4); rel1(t3mb5,t3mb4); rel1(t3mb4,t3mb3) + _q^-1 * t3mb3; ########### the inverse \tau_3 of \tau_3^- ################# t3b1:= b1;; t3b2:= qcom2(b2,b3);; #### times _q^(-1/2) t3b3:= _q * a5* b5;; t3b4:= _q^-1 * qcom2(qcom2(b4,b3),b5)+ b4*a3;; t3b5:= _q * a3 * b3;; t3b6:= qcom2(b6,b5);; #### times _q^(-1/2) t3b7:= b7;; t3a1:= a1;; t3a2:= a2*a3;; t3a3:= a5;; t3a5:= a3;; t3a6:= a6*a5;; t3a7:= a7;; ########### t3 is an algebra homomorphism ############ (_q-_q^-1)*(t3b1 * t3b7 - t3b7 * t3b1) - t3a1 + t3a7; (_q-_q^-1)* _q^-1 * (t3b2 * t3b6 - t3b6 * t3b2) - t3a2 + t3a6; (_q-_q^-1)*(t3b3 * t3b5 - t3b5 * t3b3) - t3a3 + t3a5; rel1(t3b1,t3b2); rel1(t3b2,t3b1); t3b1 * t3b3 - t3b3 * t3b1; t3b2 * t3b4 - t3b4 * t3b2; rel1(t3b2,t3b3); rel1(t3b3,t3b2); rel1(t3b3,t3b4); rel1(t3b5,t3b4); rel1(t3b4,t3b3) + _q^-1 * t3b3; ########### t3 is the inverse of t3m ############## _q^-1 * qcom2(t3b3,t3b2)-b2; _q^-1 * t3a3* t3b5 - b3; _q^-1 * qcom2(t3b3,qcom2(t3b5,t3b4))+t3b4*t3a3 - b4; _q^-1 * t3a5 * t3b3 - b5; _q^-1 * qcom2(t3b5,t3b6) - b6; t3a2*t3a3 - a2; t3a5 - a3; t3a3 - a5; t3a6*t3a5 - a6; ############ \tau_2^- braid group action ############ t2mb1:=qcom2(b2,b1);; #### times _q^(-1/2) t2mb2:= _q^-1*a2 * b6;; t2mb3:=qcom2(b2,b3);; #### times _q^(-1/2) t2mb4:=b4;; t2mb5:=qcom2(b6,b5);; #### times _q^(-1/2) t2mb6:= _q^-1 * a6 *b2;; t2mb7:=qcom2(b6,b7);; #### times _q^(-1/2) t2ma1:= a1 * a2;; t2ma2:= a6;; t2ma3:= a2 * a3;; t2ma5:= a5 * a6;; t2ma6:= a2;; t2ma7:= a6 * a7;; ################# t2m is an algebra homomorphism #################### (_q-_q^-1)* _q^-1 * (t2mb1 * t2mb7 - t2mb7 * t2mb1) - t2ma1 + t2ma7; (_q-_q^-1)*(t2mb2 * t2mb6 - t2mb6 * t2mb2) - t2ma2 + t2ma6; (_q-_q^-1)* _q^-1 * (t2mb3 * t2mb5 - t2mb5 * t2mb3) - t2ma3 + t2ma5; rel1(t2mb1,t2mb2); rel1(t2mb2,t2mb1); t2mb1 * t2mb3 - t2mb3 * t2mb1; t2mb2 * t2mb4 - t2mb4 * t2mb2; rel1(t2mb2,t2mb3); rel1(t2mb3,t2mb2); rel1(t2mb3,t2mb4); rel1(t2mb5,t2mb4); rel1(t2mb4,t2mb3) + _q^-1 * t2mb3; rel1(t2mb4,t2mb5) + _q^-1 * t2mb5; #### from here onwards it's symmetric ################ the inverse \tau_2 of \tau_2^- ##################### t2b1:= qcom2(b1,b2);; #### times _q^(-1/2) t2b2:= _q *a6 * b6;; t2b3:= qcom2(b3,b2);; #### times _q^(-1/2) t2b4:= b4;; t2b5:= qcom2(b5,b6);; #### times _q^(-1/2) t2b6:= _q * a2 *b2;; t2b7:= qcom2(b7,b6);; #### times _q^(-1/2) t2a1:= a1 * a2;; t2a2:= a6;; t2a3:= a2 * a3;; t2a5:= a5 * a6;; t2a6:= a2;; t2a7:= a6 * a7;; ################# t2 is an algebra homomorphism #################### (_q-_q^-1)* _q^-1 * (t2b1 * t2b7 - t2b7 * t2b1) - t2a1 + t2a7; (_q-_q^-1)*(t2b2 * t2b6 - t2b6 * t2b2) - t2a2 + t2a6; (_q-_q^-1)* _q^-1 * (t2b3 * t2b5 - t2b5 * t2b3) - t2a3 + t2a5; rel1(t2b1,t2b2); rel1(t2b2,t2b1); t2b1 * t2b3 - t2b3 * t2b1; t2b2 * t2b4 - t2b4 * t2b2; rel1(t2b2,t2b3); rel1(t2b3,t2b2); rel1(t2b3,t2b4); rel1(t2b5,t2b4); rel1(t2b4,t2b3) + _q^-1 * t2b3; rel1(t2b4,t2b5) + _q^-1 * t2b5; #### from here onwards it's symmetric ############### t2 is the inverse of t2m #################### _q^-1 * qcom2(t2b2,t2b1) -b1; _q^-1 *t2a2 * t2b6 -b2; _q^-1 * qcom2(t2b2,t2b3) -b3; t2b4 -b4; _q^-1 * qcom2(t2b6,t2b5) -b5; _q^-1 * t2a6 *t2b2 -b6; _q^-1 * qcom2(t2b6,t2b7) -b7; t2a1 * t2a2 - a1; t2a6 -a2; t2a2 * t2a3 -a3; t2a5 * t2a6 -a5; t2a2 -a6; t2a6 * t2a7 -a7; ############ \tau_1^- braid group action ############ t1mb1:= _q^-1 * a1 * b7;; t1mb2:= qcom2(b1,b2);; #### times _q^(-1/2) t1mb3:=b3;; t1mb4:=b4;; t1mb5:=b5;; t1mb6:= qcom2(b7,b6);; #### times _q^(-1/2) t1mb7:= _q^-1 * a7 * b1;; t1ma1:= a7;; t1ma2:= a1 *a2;; t1ma3:= a3;; t1ma5:= a5;; t1ma6:= a7* a6;; t1ma7:= a1;; ################# t1m is an algebra homomorphism #################### (_q-_q^-1)*(t1mb1 * t1mb7 - t1mb7 * t1mb1) - t1ma1 + t1ma7; (_q-_q^-1)* _q^-1 * (t1mb2 * t1mb6 - t1mb6 * t1mb2) - t1ma2 + t1ma6; (_q-_q^-1)*(t1mb3 * t1mb5 - t1mb5 * t1mb3) - t1ma3 + t1ma5; rel1(t1mb1,t1mb2); rel1(t1mb2,t1mb1); t1mb1 * t1mb3 - t1mb3 * t1mb1; t1mb2 * t1mb4 - t1mb4 * t1mb2; rel1(t1mb2,t1mb3); rel1(t1mb3,t1mb2); rel1(t1mb3,t1mb4); rel1(t1mb5,t1mb4); rel1(t1mb4,t1mb3) + _q^-1 * t1mb3; rel1(t1mb4,t1mb5) + _q^-1 * t1mb5; #### from here onwards it's symmetric ########### the inverse \tau_1 of \tau_1^- ############ t1b1:= _q * a7 * b7;; t1b2:= qcom2(b2,b1);; #### times _q^(-1/2) t1b3:=b3;; t1b4:=b4;; t1b5:=b5;; t1b6:= qcom2(b6,b7);; #### times _q^(-1/2) t1b7:= _q * a1 * b1;; t1a1:= a7;; t1a2:= a1 *a2;; t1a3:= a3;; t1a5:= a5;; t1a6:= a7* a6;; t1a7:= a1;; ################# t1 is an algebra homomorphism #################### (_q-_q^-1)*(t1b1 * t1b7 - t1b7 * t1b1) - t1a1 + t1a7; (_q-_q^-1)* _q^-1 * (t1b2 * t1b6 - t1b6 * t1b2) - t1a2 + t1a6; (_q-_q^-1)*(t1b3 * t1b5 - t1b5 * t1b3) - t1a3 + t1a5; rel1(t1b1,t1b2); rel1(t1b2,t1b1); t1b1 * t1b3 - t1b3 * t1b1; t1b2 * t1b4 - t1b4 * t1b2; rel1(t1b2,t1b3); rel1(t1b3,t1b2); rel1(t1b3,t1b4); rel1(t1b5,t1b4); rel1(t1b4,t1b3) + _q^-1 * t1b3; rel1(t1b4,t1b5) + _q^-1 * t1b5; #### from here onwards it's symmetric ############ t1m is the iverse of t1 #################### _q^-1 * t1a1 * t1b7 -b1; _q^-1 * qcom2(t1b1,t1b2) -b2; t1b3 -b3; t1b4 -b4; t1b5 -b5; _q^-1 * qcom2(t1b7,t1b6) -b6; _q^-1 * t1a7 * t1b1 -b7; t1a7 -a1; t1a1 *t1a2 -a2; t1a3 -a3; t1a5 -a5; t1a7* t1a6 -a6; t1a1 -a7; ############ braid relations for t4 and t3 ############################### ##### To simplify notation we write t434b5 instead of t4 t3 t4 (b5) ###### ##### And similar notation for other evaluations of products of t4 ###### ##### and t3 or other braid group generators ###### ########################################################################### ########### recall the definition of t3: ################################# t3b1:=b1;; t3b2:= qcom2(b2,b3);; #### times _q^(-1/2) t3b3:=_q * a5* b5;; t3b4:=_q^-1 * qcom2(qcom2(b4,b3),b5)+ b4*a3;; t3b5:=_q * a3 * b3;; t3b6:= qcom2(b6,b5);; #### times _q^(-1/2) t3b7:=b7;; t3a1:= a1;; t3a2:= a2*a3;; t3a3:= a5;; t3a5:= a3;; t3a6:= a6*a5;; t3a7:= a7;; ########### and recall the definition of t4 ############################### t4b1:=b1;; t4b2:=b2;; t4b3:=qcom2(b3,b4);; t4b4:=b4;; t4b5:=qcom2(b5,b4);; t4b6:=b6;; t4b7:=b7;; t4a1:=a1;; t4a2:=a2;; t4a3:=a3;; t4a5:=a5;; t4a6:=a6;; t4a7:=a7;; ############################################################################## #### Observe, that both t3 and t4 act as the identity on b1, a1, b7, a7 #### #### Hence we only need to consider the action on the smaller subalgebra #### #### generated by the other generators #### ############################################################################## t43b2:= qcom2(t4b2,t4b3);; #### times _q^(-1/2) t43b3:=_q * t4a5* t4b5;; t43b4:=_q^-1 * qcom2(qcom2(t4b4,t4b3),t4b5)+ t4b4*t4a3;; t43b5:=_q * t4a3 * t4b3;; t43b6:= qcom2(t4b6,t4b5);; #### times _q^(-1/2) t43a2:= t4a2*t4a3;; t43a3:= t4a5;; t43a5:= t4a3;; t43a6:= t4a6*t4a5;; ############# t34b2:=t3b2;; #### times _q^(-1/2) t34b3:=qcom2(t3b3,t3b4);; t34b4:=t3b4;; t34b5:=qcom2(t3b5,t3b4);; t34b6:=t3b6;; #### times _q^(-1/2) t34a2:=t3a2;; t34a3:=t3a3;; t34a5:=t3a5;; t34a6:=t3a6;; ############ t343b2:= qcom2(t34b2,t34b3);; #### times _q^-1 t343b3:=_q * t34a5* t34b5;; t343b4:=_q^-1 * qcom2(qcom2(t34b4,t34b3),t34b5)+ t34b4*t34a3;; t343b5:=_q * t34a3 * t34b3;; t343b6:= qcom2(t34b6,t34b5);; #### times _q^-1 t343a2:= t34a2*t34a3;; t343a3:= t34a5;; t343a5:= t34a3;; t343a6:= t34a6*t34a5;; ############# t434b2:=t43b2;; #### times _q^(-1/2) t434b3:=qcom2(t43b3,t43b4);; t434b4:=t43b4;; t434b5:=qcom2(t43b5,t43b4);; t434b6:=t43b6;; #### times _q^(-1/2) t434a2:=t43a2;; t434a3:=t43a3;; t434a5:=t43a5;; t434a6:=t43a6;; ############ t4343b2:=qcom2(t434b2,t434b3);; #### times _q^-1 t4343b3:=_q * t434a5* t434b5;; t4343b4:=_q^-1 * qcom2(qcom2(t434b4,t434b3),t434b5)+ t434b4*t434a3;; t4343b5:=_q * t434a3 * t434b3;; t4343b6:=qcom2(t434b6,t434b5);; #### times _q^-1 t4343a2:= t434a2*t434a3;; t4343a3:= t434a5;; t4343a5:= t434a3;; t4343a6:= t434a6*t434a5;; ############# t3434b2:=t343b2;; #### times _q^-1 t3434b3:=qcom2(t343b3,t343b4);; t3434b4:=t343b4;; t3434b5:=qcom2(t343b5,t343b4);; t3434b6:=t343b6;; #### times _q^-1 t3434a2:=t343a2;; t3434a3:=t343a3;; t3434a5:=t343a5;; t3434a6:=t343a6;; #################################################################### ############ final verification of the type B braid relation: ###### ############ all the followsing computations need to give 0 ###### #################################################################### t3434b2 - t4343b2; ##### times q^-1 t3434b3 - t4343b3; t3434b4 - t4343b4; t3434b5 - t4343b5; t3434b6 - t4343b6; ##### times q^-1 t3434a2 - t4343a2; t3434a3 - t4343a3; t3434a5 - t4343a5; t3434a6 - t4343a6; #################################################################### #### Now we approach the type A braid relation between t2 and ##### #### t3 in the same way, again writing t232b1 etc. ##### #################################################################### t2b1:=qcom2(b1,b2);; #### times _q^(-1/2) t2b2:= _q *a6 * b6;; t2b3:=qcom2(b3,b2);; #### times _q^(-1/2) t2b4:=b4;; t2b5:=qcom2(b5,b6);; #### times _q^(-1/2) t2b6:= _q * a2 *b2;; t2b7:=qcom2(b7,b6);; #### times _q^(-1/2) t2a1:= a1 * a2;; t2a2:= a6;; t2a3:= a2 * a3;; t2a5:= a5 * a6;; t2a6:= a2;; t2a7:= a6 * a7;; ######################### t3b1:=b1;; t3b2:=qcom2(b2,b3);; #### times _q^(-1/2) t3b3:=_q * a5* b5;; t3b4:=_q^-1 * qcom2(qcom2(b4,b3),b5)+ b4*a3;; t3b5:=_q * a3 * b3;; t3b6:=qcom2(b6,b5);; #### times _q^(-1/2) t3b7:=b7;; t3a1:= a1;; t3a2:= a2*a3;; t3a3:= a5;; t3a5:= a3;; t3a6:= a6*a5;; t3a7:= a7;; ######################### t32b1:=qcom2(t3b1,t3b2);; #### times _q^-1 t32b2:= _q * t3a6 * t3b6;; t32b3:=qcom2(t3b3,t3b2);; #### times _q^-1 t32b4:=t3b4;; t32b5:=qcom2(t3b5,t3b6);; #### times _q^-1 t32b6:= _q * t3a2 *t3b2;; t32b7:=qcom2(t3b7,t3b6);; #### times _q^-1 t32a1:= t3a1 * t3a2;; t32a2:= t3a6;; t32a3:= t3a2 * t3a3;; t32a5:= t3a5 * t3a6;; t32a6:= t3a2;; t32a7:= t3a6 * t3a7;; ######################### t23b1:=t2b1;; #### times _q^(-1/2) t23b2:=qcom2(t2b2,t2b3);; #### times _q^-1 t23b3:= _q * t2a5* t2b5;; #### times _q^(-1/2) t23b4:= _q^-2 * qcom2(qcom2(t2b4,t2b3),t2b5)+ t2b4*t2a3;; #### q^-1 entered only in first term t23b5:=_q * t2a3 * t2b3;; #### times _q^(-1/2) t23b6:=qcom2(t2b6,t2b5);; #### times _q^-1 t23b7:=t2b7;; #### times _q^(-1/2) t23a1:= t2a1;; t23a2:= t2a2*t2a3;; t23a3:= t2a5;; t23a5:= t2a3;; t23a6:= t2a6*t2a5;; t23a7:= t2a7;; ######################### t232b1:= qcom2(t23b1,t23b2);; #### times _q^-2 t232b2:= _q *t23a6 * t23b6;; #### times _q^(-1/2) t232b3:= qcom2(t23b3,t23b2);; #### times _q^-2 t232b4:=t23b4;; t232b5:= qcom2(t23b5,t23b6);; #### times _q^-2 t232b6:= _q * t23a2 *t23b2;; #### times _q^(-1/2) t232b7:= qcom2(t23b7,t23b6);; #### times _q^-2 t232a1:= t23a1 * t23a2;; t232a2:= t23a6;; t232a3:= t23a2 * t23a3;; t232a5:= t23a5 * t23a6;; t232a6:= t23a2;; t232a7:= t23a6 * t23a7;; ######################### t323b1:=t32b1;; #### times _q^-1 t323b2:=qcom2(t32b2,t32b3);; #### times _q^(-3/2) t323b3:=_q * t32a5* t32b5;; #### times _q^-1 t323b4:= _q^-3 * qcom2(qcom2(t32b4,t32b3),t32b5)+ t32b4*t32a3;; #### again _q^-1 only enters first term t323b5:=_q * t32a3 * t32b3;; #### times _q^-1 t323b6:=qcom2(t32b6,t32b5);; #### times _q^(-3/2) t323b7:=t32b7;; #### times _q^-1 t323a1:= t32a1;; t323a2:= t32a2*t32a3;; t323a3:= t32a5;; t323a5:= t32a3;; t323a6:= t32a6*t32a5;; t323a7:= t32a7;; ############################################################################### ########## Final step in the verification of the type A braid relation ######## ########## We need to take into account the differences of q-factors ######## ############################################################################### t323b1 - _q^-1 * t232b1; t323b2 - _q * t232b2; t323b3 - _q^-1 * t232b3; t323b4 - t232b4; t323b5 - _q^-1 * t232b5; t323b6 - _q * t232b6; t323b7 - _q^-1 * t232b7; t323a1 - t232a1; t323a2 - t232a2; t323a3 - t232a3; t323a5 - t232a5; t323a6 - t232a6; t323a7 - t232a7; ############################################################################### ########## We now verify the type A braid relation between t1 and t2 ######## ############################################################################### t1b1:= _q * a7 * b7;; t1b2:= qcom2(b2,b1);; #### times _q^(-1/2) t1b3:=b3;; t1b4:=b4;; t1b5:=b5;; t1b6:= qcom2(b6,b7);; #### times _q^(-1/2) t1b7:= _q * a1 * b1;; t1a1:= a7;; t1a2:= a1 *a2;; t1a3:= a3;; t1a5:= a5;; t1a6:= a7* a6;; t1a7:= a1;; ################### t2b1:=qcom2(b1,b2);; #### times _q^(-1/2) t2b2:= _q *a6 * b6;; t2b3:=qcom2(b3,b2);; #### times _q^(-1/2) t2b4:=b4;; t2b5:=qcom2(b5,b6);; #### times _q^(-1/2) t2b6:= _q * a2 *b2;; t2b7:=qcom2(b7,b6);; #### times _q^(-1/2) t2a1:= a1 * a2;; t2a2:= a6;; t2a3:= a2 * a3;; t2a5:= a5 * a6;; t2a6:= a2;; t2a7:= a6 * a7;; ##################### t21b1:= _q * t2a7 * t2b7;; #### times _q^(-1/2) t21b2:= qcom2(t2b2,t2b1);; #### times _q^-1 t21b3:=t2b3;; #### times _q^(-1/2) t21b4:=t2b4;; t21b5:=t2b5;; #### times _q^(-1/2) t21b6:= qcom2(t2b6,t2b7);; #### times _q^-1 t21b7:= _q * t2a1 * t2b1;; #### times _q^(-1/2) t21a1:= t2a7;; t21a2:= t2a1 *t2a2;; t21a3:= t2a3;; t21a5:= t2a5;; t21a6:= t2a7* t2a6;; t21a7:= t2a1;; ################### t12b1:=qcom2(t1b1,t1b2);; #### times _q^-1 t12b2:= _q *t1a6 * t1b6;; #### times _q^(-1/2) t12b3:=qcom2(t1b3,t1b2);; #### times _q^-1 t12b4:=t1b4;; t12b5:=qcom2(t1b5,t1b6);; #### times _q^-1 t12b6:= _q * t1a2 *t1b2;; #### times _q^(-1/2) t12b7:=qcom2(t1b7,t1b6);; #### times _q^-1 t12a1:= t1a1 * t1a2;; t12a2:= t1a6;; t12a3:= t1a2 * t1a3;; t12a5:= t1a5 * t1a6;; t12a6:= t1a2;; t12a7:= t1a6 * t1a7;; ##################### t121b1:= _q * t12a7 * t12b7;; #### times _q^-1 t121b2:= qcom2(t12b2,t12b1);; #### times _q^-2 t121b3:=t12b3;; #### times _q^-1 t121b4:=t12b4;; t121b5:=t12b5;; #### times _q^-1 t121b6:= qcom2(t12b6,t12b7);; #### times _q^-2 t121b7:= _q * t12a1 * t12b1;; #### times _q^-1 t121a1:= t12a7;; t121a2:= t12a1 *t12a2;; t121a3:= t12a3;; t121a5:= t12a5;; t121a6:= t12a7* t12a6;; t121a7:= t12a1;; ################### t212b1:=qcom2(t21b1,t21b2);; #### times _q^-2 t212b2:= _q *t21a6 * t21b6;; #### times _q^-1 t212b3:=qcom2(t21b3,t21b2);; #### times _q^-2 t212b4:=t21b4;; t212b5:=qcom2(t21b5,t21b6);; #### times _q^-2 t212b6:= _q * t21a2 *t21b2;; #### times _q^-1 t212b7:=qcom2(t21b7,t21b6);; #### times _q^-2 t212a1:= t21a1 * t21a2;; t212a2:= t21a6;; t212a3:= t21a2 * t21a3;; t212a5:= t21a5 * t21a6;; t212a6:= t21a2;; t212a7:= t21a6 * t21a7;; ############################################################################### ########## Final step in the verification of the type A braid relation ######## ########## between t1 and t2. ######## ########## We need to take into account the differences of q-factors ######## ############################################################################### t121b1 - _q^-1 * t212b1; t121b2 - _q * t212b2; t121b3 - _q^-1 * t212b3; t121b4 - t212b4; t121b5 - _q^-1 * t212b5; t121b6 - _q * t212b6; t121b7 - _q^-1 * t212b7; t121a1 - t212a1; t121a2 - t212a2; t121a3 - t212a3; t121a5 - t212a5; t121a6 - t212a6; t121a7 - t212a7; ####### :-) End :-) #####################################