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packages - FeynArts not working properly



So I have installed all FeynArts folders (from 3.5 to 3.7) with FeynCalc 8.0.1., and none of it is working properly :\


First I load the path to specific FeynArts package (3.5 for instance), then, by:


<< HighEnergyPhysics`FeynCalc`;

I load FeynCalc, and he says


Loading FeynCalc from C:\Users\*****\AppData\Roaming\Mathematica\Applications\HighEnergyPhysics
FeynCalc 8.1.0 For help, type ?FeynCalc, open FeynCalcRef8.nb or visit www.feyncalc.org
Loading FeynArts, see www.feynarts.de for documentation
FeynArts 3.5 patched for use with FeynCalc


So everything seems nice, right? Wrong!


I even load FeynArts package, and no errors. But when I want to initialize the proper model I get:


In[9]:= InitializeModel[SM]

During evaluation of In[9]:= 

During evaluation of In[9]:= loading generic model file C:\Users\*****\AppData\Roaming\Mathematica\Applications\HighEnergyPhysics\FeynArts-3.5\Models\Lorentz.gen

During evaluation of In[9]:= TagSetDelayed::tagnf: Tag FourVector not found in \!
\(TraditionalForm\`\(-\(TraditionalForm\`mom_\)\^\(TraditionalForm\`\(TraditionalForm\`\(Pattern[\(\(mu___, _\)\)]\)\)\)\)\)

. >>

During evaluation of In[9]:= Pattern::patvar: First element in pattern Pattern[b_,_] is not a valid pattern name. >>

During evaluation of In[9]:= Pattern::patvar: First element in pattern Pattern[b_,_] is not a valid pattern name. >>

Out[9]= $Aborted

And I can't do anything! I can plot topology, but I can't insert fields. I've been doing everything by the book :\ What seems to be wrong? :\



Answer




I've just uploaded a new version which again should support loading FeynArts, so that FeynCalc and FeynArts can be used from the same session - which I personally find very convenient.


See


http://www.feyncalc.org/download/


and


http://www.feyncalc.org/cgi-bin/diary.pl


FeynArts-3.7 is bundled with the release, so you can simply load FeynCalc with


$LoadPhi = True;
    $LoadFeynArts = True;
<< HighEnergyPhysics`FeynCalc`;


The first time you do this, FeynArts will be patched to avoid name clashes etc. After that you can in principle load FeynCalc+FeynArts without loading PHI, but then you should manually do


SetOptions[FourVector, FeynCalcInternal -> False];

before


InitializeModel[SM]

Otherwise FeynArts will complain and not load correctly


because of


FourVector /: -FourVector[mom_, mu___] := FourVector[Expand[-mom], mu]


in "Lorentz.gen".


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