Hi guys, I need to simplify tedious expressions involving products of fermionic creation/annihilation operators. I loaded the Physics package, and defined the fermionic operators c[i,spin] and C[i,spin] where i=1..4, spin=1..2 My first concern is that c[i,spin].c[i,spin] doesn't return 0, while AntiCommutator(c[i,spin],c[i,spin]) does... I don't get it. Although when I apply c[i,spin].c[i,spin] to some ket it does return 0... I'm a bit lost. Any idea?

I have a nested list, say test:=[[1,2,3,4],[5,6],[7,8,9]]: and I want to use something like map(x->1/x,test); to get [[1, 1/2, 1/3, 1/4], [1/5, 1/6], [1/7, 1/8, 1/9]] but it won't work... map doesn't go in nested lists and it rather returns [1/[1, 2, 3, 4], 1/[5, 6], 1/[7, 8, 9]] I can't find an example about this simple problem, I'm sure it must be easy though but I'm losing my mind on this one.