Operator
~
The wedge product operator is denoted by the tilde ~
. This is
a binary operator. Its arguments should be expressions involving scalars,
covariant tensors of rank one, or covariant tensors of rank l
that
have been declared antisymmetric in all covariant indices.
The behavior of the wedge product operator is controlled by the
igeowedge_flag
flag, as in the following example:
(%i1) load(itensor); (%o1) /share/tensor/itensor.lisp (%i2) ishow(a([i])~b([j]))$ a b - b a i j i j (%t2) ------------- 2 (%i3) decsym(a,2,0,[anti(all)],[]); (%o3) done (%i4) ishow(a([i,j])~b([k]))$ a b + b a - a b i j k i j k i k j (%t4) --------------------------- 3 (%i5) igeowedge_flag:true; (%o5) true (%i6) ishow(a([i])~b([j]))$ (%t6) a b - b a i j i j (%i7) ishow(a([i,j])~b([k]))$ (%t7) a b + b a - a b i j k i j k i k j