Question: problem with multiplication and Pauli matrices

I need hepl.  I work with the physics paсkage and I set:

with(Physics);
with(StandardModel);
Setup(mathematicalnotation = true)

Coordinates(X)

Define(p)

Setup(su2)

CompactDisplay(p(X))

U := 1+i*(1/f)*p[a](X)*Psigma[a]

H := v*U

DD[mu] := (d_[mu]+2*i*nu_5*KroneckerDelta[mu, 0])*Psigma[0]

And next:

Trace(DD[mu]*H*DD[mu]*H) or simplify(DD[mu]*H*DD[mu]*H)

Maple speaks:

Error, (in Physics:-Trace) invalid input: `union` received Physics:-d_[mu] = F1, which is not valid for its 1st argument

What I am doing wrong? (f, v, nu_5 is constans; a=1,2,3 and mu=0,1,2,3, Psigma[0] is unit matrix 2x2)

 

And if I write:

simplify(Trace(Psigma[a]*Psigma[a]))

Maple doesn't understand that it equals six. 

 

Please Wait...