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cfnorm_orthogonal: '[\sum_(xi <- S) nu xi] = \sum_(xi <- S) '[xi]. Proof. rewrite -(eq_bigr _ (fun _ _ => scale1r _)) cfnorm_sum_orthogonal. by apply: eq_bigr => xi; rewrite normCK conjC1 !mul1r. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
cfnorm_orthogonal
orthogonal_spanS phi : pairwise_orthogonal S -> phi \in <<S>>%VS -> {z | z = fun xi => '[phi, xi] / '[xi] & phi = \sum_(xi <- S) z xi *: xi}. Proof. move=> oSS /free_span[|c -> _]; first exact: orthogonal_free. set z := fun _ => _ : algC; exists z => //; apply: eq_big_seq => u Su. rewrite /z cfproj_sum_orthogonal // mulfK // cfnorm_eq0. by rewrite (memPn _ u Su); case/andP: oSS. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
orthogonal_span
map_orthonormal: orthonormal (map nu S). Proof. rewrite !orthonormalE map_pairwise_orthogonal // andbT. by apply/allP=> _ /mapP[xi Sxi ->]; rewrite /= Inu ?nS1 // mem_zchar. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
map_orthonormal
cfproj_sum_orthonormalz phi : phi \in S -> '[\sum_(xi <- S) z xi *: nu xi, nu phi] = z phi. Proof. by move=> Sphi; rewrite cfproj_sum_orthogonal // nS1 // mulr1. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
cfproj_sum_orthonormal
cfdot_sum_orthonormalz1 z2 : '[\sum_(xi <- S) z1 xi *: xi, \sum_(xi <- S) z2 xi *: xi] = \sum_(xi <- S) z1 xi * (z2 xi)^*. Proof. rewrite cfdot_sum_orthogonal //; apply: eq_big_seq => phi /nS1->. by rewrite mulr1. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
cfdot_sum_orthonormal
cfnorm_sum_orthonormalz : '[\sum_(xi <- S) z xi *: nu xi] = \sum_(xi <- S) `|z xi| ^+ 2. Proof. rewrite cfnorm_sum_orthogonal //. by apply: eq_big_seq => xi /nS1->; rewrite mulr1. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
cfnorm_sum_orthonormal
cfnorm_map_orthonormal: '[\sum_(xi <- S) nu xi] = (size S)%:R. Proof. by rewrite cfnorm_orthogonal // (eq_big_seq _ nS1) big_tnth sumr_const card_ord. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
cfnorm_map_orthonormal
orthonormal_spanphi : phi \in <<S>>%VS -> {z | z = fun xi => '[phi, xi] & phi = \sum_(xi <- S) z xi *: xi}. Proof. case/orthogonal_span=> // _ -> {2}->; set z := fun _ => _ : algC. by exists z => //; apply: eq_big_seq => xi /nS1->; rewrite divr1. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
orthonormal_span
cfnorm_orthonormalS : orthonormal S -> '[\sum_(xi <- S) xi] = (size S)%:R. Proof. exact: cfnorm_map_orthonormal. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
cfnorm_orthonormal
vchar_orthonormalPS : {subset S <= 'Z[irr G]} -> reflect (exists I : {set Iirr G}, exists b : Iirr G -> bool, perm_eq S [seq (-1) ^+ b i *: 'chi_i | i in I]) (orthonormal S). Proof. move=> vcS; apply: (equivP orthonormalP). split=> [[uniqS oSS] | [I [b defS]]]; last first. split=> [|xi1 xi2]; rewrite ?(perm_mem defS). rewrite (perm_uniq defS) map_inj_uniq ?enum_uniq // => i j /eqP. by rewrite eq_signed_irr => /andP[_ /eqP]. case/mapP=> [i _ ->] /mapP[j _ ->]; rewrite eq_signed_irr. rewrite cfdotZl cfdotZr rmorph_sign mulrA cfdot_irr -signr_addb mulr_natr. by rewrite mulrb andbC; case: eqP => //= ->; rewrite addbb eqxx. pose I := [set i | ('chi_i \in S) || (- 'chi_i \in S)]. pose b i := - 'chi_i \in S; exists I, b. apply: uniq_perm => // [|xi]. rewrite map_inj_uniq ?enum_uniq // => i j /eqP. by rewrite eq_signed_irr => /andP[_ /eqP]. apply/idP/mapP=> [Sxi | [i Ii ->{xi}]]; last first. move: Ii; rewrite mem_enum inE orbC -/(b i). by case b_i: (b i); rewrite (scale1r, scaleN1r). have: '[xi] = 1 by rewrite oSS ?eqxx. have vc_xi := vcS _ Sxi; rewrite cfdot_sum_irr. case/natr_sum_eq1 => [i _ | i [_ /eqP norm_xi_i xi_i'_0]]. by rewrite -normCK rpredX // natr_norm_int ?Cint_cfdot_vchar_irr. suffices def_xi: xi = (-1) ^+ b i *: 'chi_i. exists i; rewrite // mem_enum inE -/(b i) orbC. by case: (b i) def_xi Sxi => // ->; rewrite scale1r. move: Sxi; rewrite [xi]cfun_sum_cfdot (bigD1 i) //. rewrite big1 //= ?addr0 => [|j ne_ji]; last first. apply/eq ...
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
vchar_orthonormalP
vchar_norm1Pphi : phi \in 'Z[irr G] -> '[phi] = 1 -> exists b : bool, exists i : Iirr G, phi = (-1) ^+ b *: 'chi_i. Proof. move=> Zphi phiN1. have: orthonormal phi by rewrite /orthonormal/= phiN1 eqxx. case/vchar_orthonormalP=> [xi /predU1P[->|] // | I [b def_phi]]. have: phi \in (phi : seq _) := mem_head _ _. by rewrite (perm_mem def_phi) => /mapP[i _ ->]; exists (b i), i. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
vchar_norm1P
zchar_small_normphi n : phi \in 'Z[irr G] -> '[phi] = n%:R -> (n < 4)%N -> {S : n.-tuple 'CF(G) | [/\ orthonormal S, {subset S <= 'Z[irr G]} & phi = \sum_(xi <- S) xi]}. Proof. move=> Zphi def_n lt_n_4. pose S := [seq '[phi, 'chi_i] *: 'chi_i | i in irr_constt phi]. have def_phi: phi = \sum_(xi <- S) xi. rewrite big_image big_mkcond {1}[phi]cfun_sum_cfdot. by apply: eq_bigr => i _; rewrite if_neg; case: eqP => // ->; rewrite scale0r. have orthS: orthonormal S. apply/orthonormalP; split=> [|_ _ /mapP[i phi_i ->] /mapP[j _ ->]]. rewrite map_inj_in_uniq ?enum_uniq // => i j; rewrite mem_enum => phi_i _. by move/eqP; rewrite eq_scaled_irr (negbTE phi_i) => /andP[_ /= /eqP]. rewrite eq_scaled_irr cfdotZl cfdotZr cfdot_irr mulrA mulr_natr mulrb. rewrite mem_enum in phi_i; rewrite (negbTE phi_i) andbC; case: eqP => // <-. have /natrP[m def_m] := natr_norm_int (Cint_cfdot_vchar_irr i Zphi). apply/eqP; rewrite eqxx /= -normCK def_m -natrX eqr_nat eqn_leq lt0n. rewrite expn_eq0 andbT -eqC_nat -def_m normr_eq0 [~~ _]phi_i andbT. rewrite (leq_exp2r _ 1) // -ltnS -(@ltn_exp2r _ _ 2) //. apply: leq_ltn_trans lt_n_4; rewrite -leC_nat -def_n natrX. rewrite cfdot_sum_irr (bigD1 i) //= -normCK def_m addrC -subr_ge0 addrK. by rewrite sumr_ge0 // => ? _; apply: mul_conjC_ge0. have <-: size S = n. by apply/eqP; rewrite -eqC_nat -def_n def_phi cfnorm_orthonormal. exists (in_tuple S); split=> // _ /mapP[i _ ->]. by rewrite scale_zchar ?irr_vchar // Cint_cfdot_vchar_irr. ...
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
zchar_small_norm
vchar_norm2phi : phi \in 'Z[irr G, G^#] -> '[phi] = 2 -> exists i, exists2 j, j != i & phi = 'chi_i - 'chi_j. Proof. rewrite zchar_split cfunD1E => /andP[Zphi phi1_0]. case/zchar_small_norm => // [[[|chi [|xi [|?]]] //= S2]]. case=> /andP[/and3P[Nchi Nxi _] /= ochi] /allP/and3P[Zchi Zxi _]. rewrite big_cons big_seq1 => def_phi. have [b [i def_chi]] := vchar_norm1P Zchi (eqP Nchi). have [c [j def_xi]] := vchar_norm1P Zxi (eqP Nxi). have neq_ji: j != i. apply: contraTneq ochi; rewrite !andbT def_chi def_xi => ->. rewrite cfdotZl cfdotZr rmorph_sign cfnorm_irr mulr1 -signr_addb. by rewrite signr_eq0. have neq_bc: b != c. apply: contraTneq phi1_0; rewrite def_phi def_chi def_xi => ->. rewrite -scalerDr !cfunE mulf_eq0 signr_eq0 eq_le lt_geF //. by rewrite ltr_pDl ?irr1_gt0. rewrite {}def_phi {}def_chi {}def_xi !scaler_sign. case: b c neq_bc => [|] [|] // _; last by exists i, j. by exists j, i; rewrite 1?eq_sym // addrC. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
vchar_norm2
Zisometry_of_cfnorm(tauS : seq 'CF(G)) : pairwise_orthogonal S -> pairwise_orthogonal tauS -> map cfnorm tauS = map cfnorm S -> {subset tauS <= 'Z[irr G]} -> {tau : {linear 'CF(L) -> 'CF(G)} | map tau S = tauS & {in 'Z[S], isometry tau, to 'Z[irr G]}}. Proof. move=> oSS oTT /isometry_of_cfnorm[||tau defT Itau] // Z_T; exists tau => //. split=> [|_ /zchar_nth_expansion[u Zu ->]]. by apply: sub_in2 Itau; apply: zchar_span. rewrite big_seq linear_sum rpred_sum // => xi Sxi. by rewrite linearZ scale_zchar ?Z_T // -defT map_f ?mem_nth. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
Zisometry_of_cfnorm
Zisometry_of_isof : free S -> {in S, isometry f, to 'Z[irr G]} -> {tau : {linear 'CF(L) -> 'CF(G)} | {in S, tau =1 f} & {in 'Z[S], isometry tau, to 'Z[irr G]}}. Proof. move=> freeS [If Zf]; have [tau Dtau Itau] := isometry_of_free freeS If. exists tau => //; split; first by apply: sub_in2 Itau; apply: zchar_span. move=> _ /zchar_nth_expansion[a Za ->]; rewrite linear_sum rpred_sum // => i _. by rewrite linearZ rpredZ_int ?Dtau ?Zf ?mem_nth. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
Zisometry_of_iso
Zisometry_injA nu : {in 'Z[S, A] &, isometry nu} -> {in 'Z[S, A] &, injective nu}. Proof. by move/isometry_raddf_inj; apply; apply: rpredB. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
Zisometry_inj
isometry_in_zcharnu : {in S &, isometry nu} -> {in 'Z[S] &, isometry nu}. Proof. move=> Inu _ _ /zchar_nth_expansion[u Zu ->] /zchar_nth_expansion[v Zv ->]. rewrite !raddf_sum; apply: eq_bigr => j _ /=. rewrite !cfdot_suml; apply: eq_bigr => i _. by rewrite !raddfZ_int //= !cfdotZl !cfdotZr Inu ?mem_nth. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
isometry_in_zchar
cfAut_zcharS A psi : cfAut_closed u S -> psi \in 'Z[S, A] -> psi^u \in 'Z[S, A]. Proof. rewrite zchar_split => SuS /andP[/zchar_nth_expansion[z Zz Dpsi] Apsi]. rewrite zchar_split cfAut_on {}Apsi {psi}Dpsi rmorph_sum rpred_sum //= => i _. by rewrite cfAutZ_Cint // scale_zchar // mem_zchar ?SuS ?mem_nth. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
cfAut_zchar
cfAut_vcharA psi : psi \in 'Z[irr G, A] -> psi^u \in 'Z[irr G, A]. Proof. by apply: cfAut_zchar; apply: irr_aut_closed. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
cfAut_vchar
sub_aut_zcharS A psi : {subset S <= 'Z[irr G]} -> psi \in 'Z[S, A] -> psi^u \in 'Z[S, A] -> psi - psi^u \in 'Z[S, A^#]. Proof. move=> Z_S Spsi Spsi_u; rewrite zcharD1 !cfunE subr_eq0 rpredB //=. by rewrite aut_intr // Cint_vchar1 // (zchar_trans Z_S) ?(zcharW Spsi). Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
sub_aut_zchar
conjC_vcharAutchi x : chi \in 'Z[irr G] -> (u (chi x))^* = u (chi x)^*. Proof. case/vcharP=> chi1 Nchi1 [chi2 Nchi2 ->]. by rewrite !cfunE !rmorphB /= !conjC_charAut. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
conjC_vcharAut
cfdot_aut_vcharphi chi : chi \in 'Z[irr G] -> '[phi^u , chi^u] = u '[phi, chi]. Proof. by case/vcharP=> chi1 Nchi1 [chi2 Nchi2 ->]; rewrite !raddfB /= !cfdot_aut_char. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
cfdot_aut_vchar
vchar_autA chi : (chi^u \in 'Z[irr G, A]) = (chi \in 'Z[irr G, A]). Proof. rewrite !(zchar_split _ A) cfAut_on; congr (_ && _). apply/idP/idP=> [Zuchi|]; last exact: cfAut_vchar. rewrite [chi]cfun_sum_cfdot rpred_sum // => i _. rewrite scale_zchar ?irr_vchar //. by rewrite -(intr_aut u) -cfdot_aut_irr -aut_IirrE Cint_cfdot_vchar_irr. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
vchar_aut
cfConjC_vchar:= cfAut_vchar Num.conj.
Definition
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
cfConjC_vchar
cfRes_vcharphi : phi \in 'Z[irr G] -> 'Res[H] phi \in 'Z[irr H]. Proof. case/vcharP=> xi1 Nx1 [xi2 Nxi2 ->]. by rewrite raddfB rpredB ?char_vchar ?cfRes_char. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
cfRes_vchar
cfRes_vchar_onA phi : H \subset G -> phi \in 'Z[irr G, A] -> 'Res[H] phi \in 'Z[irr H, A]. Proof. rewrite zchar_split => sHG /andP[Zphi Aphi]; rewrite zchar_split cfRes_vchar //. apply/cfun_onP=> x /(cfun_onP Aphi); rewrite !cfunElock !genGid sHG => ->. exact: mul0rn. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
cfRes_vchar_on
cfInd_vcharphi : phi \in 'Z[irr H] -> 'Ind[G] phi \in 'Z[irr G]. Proof. move=> /vcharP[xi1 Nx1 [xi2 Nxi2 ->]]. by rewrite raddfB rpredB ?char_vchar ?cfInd_char. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
cfInd_vchar
sub_conjC_vcharA phi : phi \in 'Z[irr G, A] -> phi - (phi^*)%CF \in 'Z[irr G, A^#]. Proof. move=> Zphi; rewrite sub_aut_zchar ?cfAut_zchar // => _ /irrP[i ->]. exact: irr_vchar. exact: cfConjC_irr. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
sub_conjC_vchar
Frobenius_kernel_exists: [Frobenius G with complement H] -> {K : {group gT} | [Frobenius G = K ><| H]}. Proof. move=> frobG; have [_ ntiHG] := andP frobG. have [[_ sHG regGH][_ tiHG /eqP defNH]] := (normedTI_memJ_P ntiHG, and3P ntiHG). suffices /sigW[K defG]: exists K, gval K ><| H == G by exists K; apply/andP. pose K1 := G :\: cover (H^# :^: G). have oK1: #|K1| = #|G : H|. rewrite cardsD (setIidPr _); last first. rewrite cover_imset; apply/bigcupsP=> x Gx. by rewrite sub_conjg conjGid ?groupV // (subset_trans (subsetDl _ _)). rewrite (cover_partition (partition_normedTI ntiHG)) -(Lagrange sHG). by rewrite (card_support_normedTI ntiHG) (cardsD1 1%g) group1 mulSn addnK. suffices extG i: {j | {in H, 'chi[G]_j =1 'chi[H]_i} & K1 \subset cfker 'chi_j}. pose K := [group of \bigcap_i cfker 'chi_(s2val (extG i))]. have nKH: H \subset 'N(K). by apply/norms_bigcap/bigcapsP=> i _; apply: subset_trans (cfker_norm _). have tiKH: K :&: H = 1%g. apply/trivgP; rewrite -(TI_cfker_irr H) /= setIC; apply/bigcapsP=> i _. apply/subsetP=> x /setIP[Hx /bigcapP/(_ i isT)/=]; rewrite !cfkerEirr !inE. by case: (extG i) => /= j def_j _; rewrite !def_j. exists K; rewrite sdprodE // eqEcard TI_cardMg // mul_subG //=; last first. by rewrite (bigcap_min (0 : Iirr H)) ?cfker_sub. rewrite -(Lagrange sHG) mulnC leq_pmul2r // -oK1 subset_leq_card //. by apply/bigcapsP=> i _; case: (extG i). case i0: (i == 0). exists 0 => [x Hx|]; last by rewrite irr0 cfker_cfun1 subsetDl. by rewri ...
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
Frobenius_kernel_exists
dirr(gT : finGroupType) (B : {set gT}) : {pred 'CF(B)} := [pred f | (f \in irr B) || (- f \in irr B)]. Arguments dirr {gT}.
Definition
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dirr
Definition_ := GRing.isOppClosed.Build (classfun G) (dirr G) dirr_oppr_closed.
HB.instance
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
Definition
dirr_oppv : (- v \in dirr G) = (v \in dirr G). Proof. exact: rpredN. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dirr_opp
dirr_signn v : ((-1)^+ n *: v \in dirr G) = (v \in dirr G). Proof. exact: rpredZsign. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dirr_sign
irr_dirri : 'chi_i \in dirr G. Proof. by rewrite !inE mem_irr. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
irr_dirr
dirrPf : reflect (exists b : bool, exists i, f = (-1) ^+ b *: 'chi_i) (f \in dirr G). Proof. apply: (iffP idP) => [| [b [i ->]]]; last by rewrite dirr_sign irr_dirr. case/orP=> /irrP[i Hf]; first by exists false, i; rewrite scale1r. by exists true, i; rewrite scaleN1r -Hf opprK. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dirrP
dirrEphi : phi \in dirr G = (phi \in 'Z[irr G]) && ('[phi] == 1). Proof. apply/dirrP/andP=> [[b [i ->]] | [Zphi /eqP/vchar_norm1P]]; last exact. by rewrite rpredZsign irr_vchar cfnorm_sign cfnorm_irr. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dirrE
cfdot_dirrf g : f \in dirr G -> g \in dirr G -> '[f, g] = (if f == - g then -1 else (f == g)%:R). Proof. case/dirrP=> [b1 [i1 ->]] /dirrP[b2 [i2 ->]]. rewrite cfdotZl cfdotZr rmorph_sign mulrA -signr_addb cfdot_irr. rewrite -scaleNr -signrN !eq_scaled_irr signr_eq0 !(inj_eq signr_inj) /=. by rewrite -!negb_add addbN mulr_sign -mulNrn mulrb; case: ifP. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
cfdot_dirr
dirr_norm1phi : phi \in 'Z[irr G] -> '[phi] = 1 -> phi \in dirr G. Proof. by rewrite dirrE => -> -> /=. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dirr_norm1
dirr_autu phi : (cfAut u phi \in dirr G) = (phi \in dirr G). Proof. rewrite !dirrE vchar_aut; apply: andb_id2l => /cfdot_aut_vchar->. exact: fmorph_eq1. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dirr_aut
dIirr(B : {set gT}) := (bool * (Iirr B))%type.
Definition
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dIirr
dirr1(B : {set gT}) : dIirr B := (false, 0).
Definition
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dirr1
ndirr(B : {set gT}) (i : dIirr B) : dIirr B := (~~ i.1, i.2).
Definition
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
ndirr
ndirr_diff(i : dIirr G) : ndirr i != i. Proof. by case: i => [] [|] i. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
ndirr_diff
ndirrK: involutive (@ndirr G). Proof. by move=> [b i]; rewrite /ndirr /= negbK. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
ndirrK
ndirr_inj: injective (@ndirr G). Proof. exact: (inv_inj ndirrK). Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
ndirr_inj
dchi(B : {set gT}) (i : dIirr B) : 'CF(B) := (-1)^+ i.1 *: 'chi_i.2.
Definition
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dchi
dchi1: dchi (dirr1 G) = 1. Proof. by rewrite /dchi scale1r irr0. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dchi1
dirr_dchii : dchi i \in dirr G. Proof. by apply/dirrP; exists i.1; exists i.2. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dirr_dchi
dIrrPphi : reflect (exists i, phi = dchi i) (phi \in dirr G). Proof. by apply: (iffP idP)=> [/dirrP[b]|] [i ->]; [exists (b, i) | apply: dirr_dchi]. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dIrrP
dchi_ndirrE(i : dIirr G) : dchi (ndirr i) = - dchi i. Proof. by case: i => [b i]; rewrite /ndirr /dchi signrN scaleNr. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dchi_ndirrE
cfdot_dchi(i j : dIirr G) : '[dchi i, dchi j] = (i == j)%:R - (i == ndirr j)%:R. Proof. case: i => bi i; case: j => bj j; rewrite cfdot_dirr ?dirr_dchi // !xpair_eqE. rewrite -dchi_ndirrE !eq_scaled_irr signr_eq0 !(inj_eq signr_inj) /=. by rewrite -!negb_add addbN negbK; case: andP => [[->]|]; rewrite ?subr0 ?add0r. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
cfdot_dchi
dchi_vchari : dchi i \in 'Z[irr G]. Proof. by case: i => b i; rewrite rpredZsign irr_vchar. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dchi_vchar
cfnorm_dchi(i : dIirr G) : '[dchi i] = 1. Proof. by case: i => b i; rewrite cfnorm_sign cfnorm_irr. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
cfnorm_dchi
dirr_inj: injective (@dchi G). Proof. case=> b1 i1 [b2 i2] /eqP; rewrite eq_scaled_irr (inj_eq signr_inj) /=. by rewrite signr_eq0 -xpair_eqE => /eqP. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dirr_inj
dirr_dIirr(B : {set gT}) J (f : J -> 'CF(B)) j : dIirr B := odflt (dirr1 B) [pick i | dchi i == f j].
Definition
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dirr_dIirr
dirr_dIirrPEJ (f : J -> 'CF(G)) (P : pred J) : (forall j, P j -> f j \in dirr G) -> forall j, P j -> dchi (dirr_dIirr f j) = f j. Proof. rewrite /dirr_dIirr => dirrGf j Pj; case: pickP => [i /eqP //|]. by have /dIrrP[i-> /(_ i)/eqP] := dirrGf j Pj. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dirr_dIirrPE
dirr_dIirrEJ (f : J -> 'CF(G)) : (forall j, f j \in dirr G) -> forall j, dchi (dirr_dIirr f j) = f j. Proof. by move=> dirrGf j; apply: (@dirr_dIirrPE _ _ xpredT). Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dirr_dIirrE
dirr_constt(B : {set gT}) (phi: 'CF(B)) : {set (dIirr B)} := [set i | 0 < '[phi, dchi i]].
Definition
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dirr_constt
dirr_consttE(phi : 'CF(G)) (i : dIirr G) : (i \in dirr_constt phi) = (0 < '[phi, dchi i]). Proof. by rewrite inE. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dirr_consttE
Cnat_dirr(phi : 'CF(G)) i : phi \in 'Z[irr G] -> i \in dirr_constt phi -> '[phi, dchi i] \in Num.nat. Proof. move=> PiZ; rewrite natrEint dirr_consttE andbC => /ltW -> /=. by case: i => b i; rewrite cfdotZr rmorph_sign rpredMsign Cint_cfdot_vchar_irr. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
Cnat_dirr
dirr_constt_oppr(i : dIirr G) (phi : 'CF(G)) : (i \in dirr_constt (-phi)) = (ndirr i \in dirr_constt phi). Proof. by rewrite !dirr_consttE dchi_ndirrE cfdotNl cfdotNr. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dirr_constt_oppr
dirr_constt_oppI(phi: 'CF(G)) : dirr_constt phi :&: dirr_constt (-phi) = set0. Proof. apply/setP=> i; rewrite inE !dirr_consttE cfdotNl inE. apply/idP=> /andP [L1 L2]; have := ltr_pDl L1 L2. by rewrite subrr lt_def eqxx. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dirr_constt_oppI
dirr_constt_oppl(phi: 'CF(G)) i : i \in dirr_constt phi -> (ndirr i) \notin dirr_constt phi. Proof. by rewrite !dirr_consttE dchi_ndirrE cfdotNr oppr_gt0 => /ltW /le_gtF ->. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dirr_constt_oppl
to_dirr(B : {set gT}) (phi : 'CF(B)) (i : Iirr B) : dIirr B := ('[phi, 'chi_i] < 0, i).
Definition
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
to_dirr
of_irr(B : {set gT}) (i : dIirr B) : Iirr B := i.2.
Definition
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
of_irr
irr_constt_to_dirr(phi: 'CF(G)) i : phi \in 'Z[irr G] -> (i \in irr_constt phi) = (to_dirr phi i \in dirr_constt phi). Proof. move=> Zphi; rewrite irr_consttE dirr_consttE cfdotZr rmorph_sign /=. by rewrite -real_normrEsign ?normr_gt0 ?Rreal_int // Cint_cfdot_vchar_irr. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
irr_constt_to_dirr
to_dirrK(phi: 'CF(G)) : cancel (to_dirr phi) (@of_irr G). Proof. by []. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
to_dirrK
of_irrK(phi: 'CF(G)) : {in dirr_constt phi, cancel (@of_irr G) (to_dirr phi)}. Proof. case=> b i; rewrite dirr_consttE cfdotZr rmorph_sign /= /to_dirr mulr_sign. by rewrite fun_if oppr_gt0; case: b => [|/ltW/le_gtF] ->. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
of_irrK
cfdot_todirrE(phi: 'CF(G)) i (phi_i := dchi (to_dirr phi i)) : '[phi, phi_i] *: phi_i = '[phi, 'chi_i] *: 'chi_i. Proof. by rewrite cfdotZr rmorph_sign mulrC -scalerA signrZK. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
cfdot_todirrE
cfun_sum_dconstt(phi : 'CF(G)) : phi \in 'Z[irr G] -> phi = \sum_(i in dirr_constt phi) '[phi, dchi i] *: dchi i. Proof. move=> PiZ; rewrite [LHS]cfun_sum_constt. rewrite (reindex (to_dirr phi))=> [/= |]; last first. by exists (@of_irr _)=> //; apply: of_irrK . by apply: eq_big => i; rewrite ?irr_constt_to_dirr // cfdot_todirrE. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
cfun_sum_dconstt
cnorm_dconstt(phi : 'CF(G)) : phi \in 'Z[irr G] -> '[phi] = \sum_(i in dirr_constt phi) '[phi, dchi i] ^+ 2. Proof. move=> PiZ; rewrite {1 2}(cfun_sum_dconstt PiZ). rewrite cfdot_suml; apply: eq_bigr=> i IiD. rewrite cfdot_sumr (bigD1 i) //= big1 ?addr0 => [|j /andP [JiD IdJ]]. rewrite cfdotZr cfdotZl cfdot_dchi eqxx eq_sym (negPf (ndirr_diff i)). by rewrite subr0 mulr1 aut_natr ?Cnat_dirr. rewrite cfdotZr cfdotZl cfdot_dchi eq_sym (negPf IdJ) -natrB ?mulr0 //. by rewrite (negPf (contraNneq _ (dirr_constt_oppl JiD))) => // <-. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
cnorm_dconstt
dirr_small_norm(phi : 'CF(G)) n : phi \in 'Z[irr G] -> '[phi] = n%:R -> (n < 4)%N -> [/\ #|dirr_constt phi| = n, dirr_constt phi :&: dirr_constt (- phi) = set0 & phi = \sum_(i in dirr_constt phi) dchi i]. Proof. move=> PiZ Pln; rewrite ltnNge -leC_nat => Nl4. suffices Fd i: i \in dirr_constt phi -> '[phi, dchi i] = 1. split; last 2 [by apply/setP=> u; rewrite !inE cfdotNl oppr_gt0 lt_asym]. apply/eqP; rewrite -eqC_nat -sumr_const -Pln (cnorm_dconstt PiZ). by apply/eqP/eq_bigr=> i Hi; rewrite Fd // expr1n. rewrite {1}[phi]cfun_sum_dconstt //. by apply: eq_bigr => i /Fd->; rewrite scale1r. move=> IiD; apply: contraNeq Nl4 => phi_i_neq1. rewrite -Pln cnorm_dconstt // (bigD1 i) ?ler_wpDr ?sumr_ge0 //=. by move=> j /andP[JiD _]; rewrite exprn_ge0 ?natr_ge0 ?Cnat_dirr. have /natrP[m Dm] := Cnat_dirr PiZ IiD; rewrite Dm -natrX ler_nat (leq_sqr 2). by rewrite ltn_neqAle eq_sym -eqC_nat -ltC_nat -Dm phi_i_neq1 -dirr_consttE. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
dirr_small_norm
cfdot_sum_dchi(phi1 phi2 : 'CF(G)) : '[\sum_(i in dirr_constt phi1) dchi i, \sum_(i in dirr_constt phi2) dchi i] = #|dirr_constt phi1 :&: dirr_constt phi2|%:R - #|dirr_constt phi1 :&: dirr_constt (- phi2)|%:R. Proof. rewrite addrC (big_setID (dirr_constt (- phi2))) /= cfdotDl; congr (_ + _). rewrite cfdot_suml -sumr_const -sumrN; apply: eq_bigr => i /setIP[p1i p2i]. rewrite cfdot_sumr (bigD1 (ndirr i)) -?dirr_constt_oppr //= dchi_ndirrE. rewrite cfdotNr cfnorm_dchi big1 ?addr0 // => j /andP[p2j i'j]. rewrite cfdot_dchi -(inv_eq ndirrK) [in rhs in - rhs]eq_sym (negPf i'j) subr0. rewrite (negPf (contraTneq _ p2i)) // => ->. by rewrite dirr_constt_oppr dirr_constt_oppl. rewrite cfdot_sumr (big_setID (dirr_constt phi1)) setIC /= addrC. rewrite big1 ?add0r => [|j /setDP[p2j p1'j]]; last first. rewrite cfdot_suml big1 // => i /setDP[p1i p2'i]. rewrite cfdot_dchi (negPf (contraTneq _ p1i)) => [|-> //]. rewrite (negPf (contraNneq _ p2'i)) ?subrr // => ->. by rewrite dirr_constt_oppr ndirrK. rewrite -sumr_const; apply: eq_bigr => i /setIP[p1i p2i]; rewrite cfdot_suml. rewrite (bigD1 i) /=; last by rewrite inE dirr_constt_oppr dirr_constt_oppl. rewrite cfnorm_dchi big1 ?addr0 // => j /andP[/setDP[p1j _] i'j]. rewrite cfdot_dchi (negPf i'j) (negPf (contraTneq _ p1j)) ?subrr // => ->. exact: dirr_constt_oppl. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
cfdot_sum_dchi
cfdot_dirr_eq1: {in dirr G &, forall phi psi, ('[phi, psi] == 1) = (phi == psi)}. Proof. move=> _ _ /dirrP[b1 [i1 ->]] /dirrP[b2 [i2 ->]]. rewrite eq_signed_irr cfdotZl cfdotZr rmorph_sign cfdot_irr mulrA -signr_addb. rewrite pmulrn -rmorphMsign (eqr_int _ _ 1) -negb_add. by case: (b1 (+) b2) (i1 == i2) => [] []. Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
cfdot_dirr_eq1
cfdot_add_dirr_eq1: {in dirr G & &, forall phi1 phi2 psi, '[phi1 + phi2, psi] = 1 -> psi = phi1 \/ psi = phi2}. Proof. move=> _ _ _ /dirrP[b1 [i1 ->]] /dirrP[b2 [i2 ->]] /dirrP[c [j ->]] /eqP. rewrite cfdotDl !cfdotZl !cfdotZr !rmorph_sign !cfdot_irr !mulrA -!signr_addb. rewrite 2!{1}signrE !mulrBl !mul1r -!natrM addrCA -subr_eq0 -!addrA. rewrite -!opprD addrA subr_eq0 -mulrSr -!natrD eqr_nat => eq_phi_psi. apply/pred2P; rewrite /= !eq_signed_irr -!negb_add !(eq_sym j) !(addbC c). by case: (i1 == j) eq_phi_psi; case: (i2 == j); do 2!case: (_ (+) c). Qed.
Lemma
character
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun eqtype ssrnat seq path", "From mathcomp Require Import div choice fintype tuple finfun bigop prime order", "From mathcomp Require Import ssralg poly finset fingroup morphism perm", "From mathcomp Require Import autom...
character/vcharacter.v
cfdot_add_dirr_eq1
RecordisComplex L of GRing.ClosedField L := { conj : {rmorphism L -> L}; conjK : involutive conj; conj_nt : ~ conj =1 id }. HB.builders Context L of isComplex L.
HB.factory
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
Record
nz2: 2 != 0 :> L. Proof. apply/eqP=> pchar2; apply: conj_nt => e; apply/eqP/idPn=> eJ. have opp_id x: - x = x :> L. by apply/esym/eqP; rewrite -addr_eq0 -mulr2n -mulr_natl pchar2 mul0r. have{} pchar2: 2%N \in [pchar L] by apply/eqP. without loss{eJ} eJ: e / conj e = e + 1. move/(_ (e / (e + conj e))); apply. rewrite fmorph_div rmorphD /= conjK -{1}[conj e](addNKr e) mulrDl. by rewrite opp_id (addrC e) divff // addr_eq0 opp_id. pose a := e * conj e; have aJ: conj a = a by rewrite rmorphM /= conjK mulrC. have [w Dw] := @solve_monicpoly _ 2%N (nth 0 [:: e * a; - 1]) isT. have{} Dw: w ^+ 2 + w = e * a. by rewrite Dw !big_ord_recl big_ord0 /= mulr1 mulN1r addr0 subrK. pose b := w + conj w; have bJ: conj b = b by rewrite rmorphD /= conjK addrC. have Db2: b ^+ 2 + b = a. rewrite -pFrobenius_autE // rmorphD addrACA Dw /= pFrobenius_autE -rmorphXn. by rewrite -rmorphD Dw rmorphM /= aJ eJ -mulrDl -{1}[e]opp_id addKr mul1r. have /eqP[] := oner_eq0 L; apply: (addrI b); rewrite addr0 -{2}bJ. have: (b + e) * (b + conj e) == 0.
Lemma
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
nz2
mul2I: injective (fun z : L => z *+ 2). Proof. have nz2 := nz2. by move=> x y; rewrite /= -mulr_natl -(mulr_natl y) => /mulfI->. Qed.
Lemma
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
mul2I
sqrtx : L := sval (sig_eqW (@solve_monicpoly _ 2%N (nth 0 [:: x]) isT)).
Definition
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
sqrt
sqrtKx: sqrt x ^+ 2 = x. Proof. rewrite /sqrt; case: sig_eqW => /= y ->. by rewrite !big_ord_recl big_ord0 /= mulr1 mul0r !addr0. Qed.
Lemma
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
sqrtK
sqrtEx y: y ^+ 2 = x -> {b : bool | y = (-1) ^+ b * sqrt x}. Proof. move=> Dx; exists (y != sqrt x); apply/eqP; rewrite mulr_sign if_neg. by case: ifPn => //; apply/implyP; rewrite implyNb -eqf_sqr Dx sqrtK. Qed.
Lemma
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
sqrtE
i:= sqrt (- 1).
Definition
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
i
sqrMix: (i * x) ^+ 2 = - x ^+ 2. Proof. by rewrite exprMn sqrtK mulN1r. Qed.
Lemma
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
sqrMi
iJ: conj i = - i. Proof. have nz2 := nz2. have /sqrtE[b]: conj i ^+ 2 = - 1 by rewrite -rmorphXn /= sqrtK rmorphN1. rewrite mulr_sign -/i; case: b => // Ri. case: conj_nt => z; wlog zJ: z / conj z = - z. move/(_ (z - conj z)); rewrite !rmorphB conjK opprB => zJ. by apply/mul2I/(canRL (subrK _)); rewrite -addrA zJ // addrC subrK. have [-> | nz_z] := eqVneq z 0; first exact: rmorph0. have [u Ru [v Rv Dz]]: exists2 u, conj u = u & exists2 v, conj v = v & (u + z * v) ^+ 2 = z. - pose y := sqrt z; exists ((y + conj y) / 2). by rewrite fmorph_div rmorphD /= conjK addrC rmorph_nat. exists ((y - conj y) / (z *+ 2)). rewrite fmorph_div rmorphMn /= zJ mulNrn invrN mulrN -mulNr rmorphB opprB. by rewrite conjK. rewrite -(mulr_natl z) invfM (mulrC z) !mulrA divfK // -mulrDl addrACA.
Lemma
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
iJ
normx := sqrt x * conj (sqrt x).
Definition
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
norm
normKx : norm x ^+ 2 = x * conj x. Proof. by rewrite exprMn -rmorphXn sqrtK. Qed.
Lemma
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
normK
normEx y : y ^+ 2 = x -> norm x = y * conj y. Proof. rewrite /norm => /sqrtE[b /(canLR (signrMK b)) <-]. by rewrite !rmorphM /= rmorph_sign mulrACA -mulrA signrMK. Qed.
Lemma
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
normE
norm_eq0x : norm x = 0 -> x = 0. Proof. by move/eqP; rewrite mulf_eq0 fmorph_eq0 -mulf_eq0 -expr2 sqrtK => /eqP. Qed.
Lemma
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
norm_eq0
normMx y : norm (x * y) = norm x * norm y. Proof. by rewrite mulrACA -rmorphM; apply: normE; rewrite exprMn !sqrtK. Qed.
Lemma
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
normM
normNx : norm (- x) = norm x. Proof. by rewrite -mulN1r normM {1}/norm iJ mulrN -expr2 sqrtK opprK mul1r. Qed.
Lemma
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
normN
lex y := norm (y - x) == y - x.
Definition
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
le
ltx y := (y != x) && le x y.
Definition
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
lt
posEx: le 0 x = (norm x == x). Proof. by rewrite /le subr0. Qed.
Lemma
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
posE
leBx y: le x y = le 0 (y - x). Proof. by rewrite posE. Qed.
Lemma
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
leB
posPx : reflect (exists y, x = y * conj y) (le 0 x). Proof. rewrite posE; apply: (iffP eqP) => [Dx | [y {x}->]]; first by exists (sqrt x). by rewrite (normE (normK y)) rmorphM /= conjK (mulrC (conj _)) -expr2 normK. Qed.
Lemma
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
posP
posJx : le 0 x -> conj x = x. Proof. by case/posP=> {x}u ->; rewrite rmorphM /= conjK mulrC. Qed.
Lemma
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
posJ
pos_linearx y : le 0 x -> le 0 y -> le x y || le y x. Proof. move=> pos_x pos_y; rewrite leB -opprB orbC leB !posE normN -eqf_sqr. by rewrite normK rmorphB !posJ ?subrr. Qed.
Lemma
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
pos_linear
sposDlx y : lt 0 x -> le 0 y -> lt 0 (x + y). Proof. have sqrtJ z : le 0 z -> conj (sqrt z) = sqrt z. rewrite posE -{2}[z]sqrtK -subr_eq0 -mulrBr mulf_eq0 subr_eq0. by case/pred2P=> ->; rewrite ?rmorph0. case/andP=> nz_x /sqrtJ uJ /sqrtJ vJ. set u := sqrt x in uJ; set v := sqrt y in vJ; pose w := u + i * v. have ->: x + y = w * conj w. rewrite rmorphD rmorphM /= iJ uJ vJ mulNr mulrC -subr_sqr sqrMi opprK. by rewrite !sqrtK. apply/andP; split; last by apply/posP; exists w. rewrite -normK expf_eq0 //=; apply: contraNneq nz_x => /norm_eq0 w0. rewrite -[x]sqrtK expf_eq0 /= -/u -(inj_eq mul2I) !mulr2n -{2}(rmorph0 conj). by rewrite -w0 rmorphD rmorphM /= iJ uJ vJ mulNr addrACA subrr addr0. Qed.
Lemma
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
sposDl
sposDx y : lt 0 x -> lt 0 y -> lt 0 (x + y). Proof. by move=> x_gt0 /andP[_]; apply: sposDl. Qed.
Lemma
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
sposD
normDx y : le (norm (x + y)) (norm x + norm y). Proof. have sposM u v: lt 0 u -> le 0 (u * v) -> le 0 v. by rewrite /lt !posE normM andbC => /andP[/eqP-> /mulfI/inj_eq->]. have posD u v: le 0 u -> le 0 v -> le 0 (u + v). have [-> | nz_u u_ge0 v_ge0] := eqVneq u 0; first by rewrite add0r. by have /andP[]: lt 0 (u + v) by rewrite sposDl // /lt nz_u. have le_sqr u v: conj u = u -> le 0 v -> le (u ^+ 2) (v ^+ 2) -> le u v. case: (eqVneq u 0) => [-> //|nz_u Ru v_ge0]. have [u_gt0 | u_le0 _] := boolP (lt 0 u). by rewrite leB (leB u) subr_sqr mulrC addrC; apply: sposM; apply: sposDl. rewrite leB posD // posE normN -addr_eq0; apply/eqP. rewrite /lt nz_u posE -subr_eq0 in u_le0; apply: (mulfI u_le0). by rewrite mulr0 -subr_sqr normK Ru subrr. have pos_norm z: le 0 (norm z) by apply/posP; exists (sqrt z). rewrite le_sqr ?posJ ?posD // sqrrD !normK -normM rmorphD mulrDl !mulrDr. rewrite addrA addrC !addrA -(addrC (y * conj y)) !addrA. move: (y * _ + _) => u; rewrite -!addrA leB opprD addrACA {u}subrr add0r -leB. rewrite {}le_sqr ?posD //. by rewrite rmorphD !rmorphM /= !conjK addrC (mulrC x) (mulrC y). rewrite -mulr2n -mulr_natr exprMn normK -natrX mulr_natr sqrrD mulrACA. rewrite -rmorphM (mulrC y x) addrAC leB mulrnA mulr2n opprD addrACA. rewrite subrr addr0 {2}(mulrC x) rmorphM mulrACA -opprB addrAC -sqrrB -sqrMi. apply/posP; exists (i * (x * conj y - y * conj x)); congr (_ * _). rewrite !(rmorphM, rmorphB) iJ !conjK mulN ...
Lemma
field
[ "From HB Require Import structures", "From mathcomp Require Import ssreflect ssrbool ssrfun ssrnat eqtype seq choice", "From mathcomp Require Import div fintype path bigop finset prime order ssralg", "From mathcomp Require Import poly polydiv mxpoly generic_quotient countalg", "From mathcomp Require Import ...
field/algC.v
normD