Fixed a bug in FCFADiracChainJoin (issue #143, thanks to Turgon).

FeynCalc · Nov 1, 2021 · d5daa37 · d5daa37
1 parent b045838
commit d5daa37
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Showing 4 changed files with 27 additions and 6 deletions.
diff --git a/FeynCalc/Dirac/FCChargeConjugateTransposed.m b/FeynCalc/Dirac/FCChargeConjugateTransposed.m
@@ -178,7 +178,7 @@
 		];
 
 		FCPrint[1, "FCChargeConjugateTransposed: Leaving.", FCDoControl->fcctVerbose];
-		FCPrint[3, "FCChargeConjugateTransposed: Leaving with", res, FCDoControl->fcctVerbose];
+		FCPrint[3, "FCChargeConjugateTransposed: Leaving with ", res, FCDoControl->fcctVerbose];
 
 		res
 
@@ -206,6 +206,10 @@
 cctEvaluateSingle[c1_. d_DiracGamma + c2_:0]:=
 		(- c1 d + c2)/; NonCommFreeQ[{c1,c2}] && FreeQ[{c1,c2}, dotHold] && !MatchQ[d,DiracGamma[5|6|7]];
 
+(*at this point we may fish out commutative prefactors*)
+cctEvaluateSingle[c_ d_dotHold]:=
+	c cctEvaluateSingle[d]/; NonCommFreeQ[c];
+
 cctEvaluateMultiple[dotHold[a_]]:=
 	cctEvaluateSingle[a];
 

diff --git a/FeynCalc/Feynman/FCFADiracChainJoin.m b/FeynCalc/Feynman/FCFADiracChainJoin.m
@@ -166,11 +166,11 @@
 
 (* A_ai B_bi -> (A. C B^T C^-1)_ab *)
 diracChainEvalM[rest_. DiracChain[chain1_,a_DiracIndex,i_DiracIndex] DiracChain[chain2_,b_DiracIndex,i_DiracIndex]]:=
-	diracChainEvalM[rest DiracChain[DOT[chain1,FCCCT[chain2, Explicit->True, FCDiracIsolate->False, FCI->True]],a,b]]/; a=!=i && b=!=i;
+	diracChainEvalM[rest DiracChain[DOT[chain1,FCCCT[chain2, Explicit->True, FCDiracIsolate->True, FCI->True]],a,b]]/; a=!=i && b=!=i;
 
 (* A_ia B_ib -> (C A^T C^-1)_ab *)
 diracChainEvalM[rest_. DiracChain[chain1_,i_DiracIndex,a_DiracIndex] DiracChain[chain2_,i_DiracIndex,b_DiracIndex]]:=
-	diracChainEvalM[rest DiracChain[DOT[FCCCT[chain1, Explicit->True, FCDiracIsolate->False, FCI->True],chain2],a,b]]/; a=!=i && b=!=i;
+	diracChainEvalM[rest DiracChain[DOT[FCCCT[chain1, Explicit->True, FCDiracIsolate->True, FCI->True],chain2],a,b]]/; a=!=i && b=!=i;
 
 (* A_ii -> Tr(A) *)
 diracChainEvalM[rest_. DiracChain[chain_/;chain=!=1,i_DiracIndex,i_DiracIndex]]:=
@@ -197,7 +197,7 @@
 
 (* u_i v_j A_ij -> ubar.A.v or vbar.A.u *)
 diracChainEvalS[rest_. DiracChain[S: Spinor[_. m1_Momentum, ___], a_DiracIndex] DiracChain[z_, a_DiracIndex, b_DiracIndex] DiracChain[Spinor[s_. m2_Momentum, r___], b_DiracIndex]]:=
-	diracChainEvalS[rest ordering[First[m2],First[m1]]] FCCCT[DOT[S, z, Spinor[-s m2, r]], Explicit->True, FCDiracIsolate->False, FCI->True]/; MemberQ[optFirst, Spinor[s m2, r]];
+	diracChainEvalS[rest ordering[First[m2],First[m1]]] FCCCT[DOT[S, z, Spinor[-s m2, r]], Explicit->True, FCDiracIsolate->True, FCI->True]/; MemberQ[optFirst, Spinor[s m2, r]];
 
 diracChainEvalS[rest_. ordering[a__] ordering[b__]]:=
 	diracChainEvalS[rest ordering[a,b]];

diff --git a/Tests/Dirac/FCChargeConjugateTransposed.test b/Tests/Dirac/FCChargeConjugateTransposed.test
@@ -103,6 +103,10 @@ Explicit -> False, FeynCalcExternal -> True]"},
 {"fcstFCChargeConjugateTransposed-ID26","FCCCT[GA[i] == x, Explicit -> True, FCE -> True]",
 "-GA[i] == x"},
 {"fcstFCChargeConjugateTransposed-ID27","FCCCT[{GA[i], GS[p]}, Explicit -> True, FCE -> True]",
-"{-GA[i], -GS[p]}"}
+"{-GA[i], -GS[p]}"},
+{"fcstFCChargeConjugateTransposed-ID28","FCChargeConjugateTransposed[-DiracGamma[7] .
+DiracGamma[LorentzIndex[Lor1]], Explicit -> True,
+FCDiracIsolate -> False, FCI -> True, FCE -> True]",
+"GA[Lor1] . GA[7]"}
 });
 
diff --git a/Tests/Feynman/FCFADiracChainJoin.test b/Tests/Feynman/FCFADiracChainJoin.test
@@ -178,7 +178,20 @@ Lor2] (C1 SDF[Col5, Col8] SDF[Col7, colInS] +
 	C2 SDF[Col5, Col7] SDF[Col8, colInS]) (C2 SDF[Col6, colOutS] SDF[
 	Col8, colOutB] +
 	C1 SDF[Col6, Col8] SDF[colOutB, colOutS]) SUNTF[{Glu5}, Col5,
-Col6] SUNTF[{Glu5}, colInB, Col7]"}
+Col6] SUNTF[{Glu5}, colInB, Col7]"},
+{"fcstFCFADiracChainJoin-ID6","FCFADiracChainJoin[{DiracChain[Spinor[-Momentum[InMom1], mqu, 1],
+	DiracIndex[Dir1]] DiracChain[Spinor[-Momentum[InMom2], mqu, 1],
+	DiracIndex[Dir2]] DiracChain[
+	mqu + DiracGamma[Momentum[InMom2 - OutMom3]], DiracIndex[Dir5],
+	DiracIndex[Dir6]] DiracChain[
+	DiracGamma[Momentum[-OutMom1 - OutMom2]] .
+	DiracGamma[LorentzIndex[Lor2]] . DiracGamma[7], DiracIndex[Dir5],
+	DiracIndex[Dir1]] DiracChain[
+	DiracGamma[LorentzIndex[Lor1]] . DiracGamma[7], DiracIndex[Dir2],
+	DiracIndex[Dir6]]}, FCE -> True]",
+"{Spinor[-Momentum[InMom2], mqu, 1] . GA[Lor1] .
+GA[7] . (mqu - GS[InMom2 - OutMom3]) . GS[-OutMom1 - OutMom2] .
+GA[Lor2] . GA[7] . Spinor[Momentum[InMom1], mqu, 1]}"}
 };