This book [1] uses an interesting notation for change of basis calculations where the two bases are distinguished by priming the indices.
Suppose for some -dimensional vector space
we have an original basis
and a primed basis
(of course, the choice
of calling one basis the original the other primed is arbitrary). There
are linear transformations from each basis to the other:

Note that the position of the prime matters: if we consider and
as matrices, they would be two
different matrices. In fact, they would be inverses. Using the
fact that
for
:

How does the dual basis transform between and
? Since each
is itself a
covector, we can express it in terms of its components
in the original dual basis:
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(2) |
Then we determine what the are by
evaluating
on the basis vectors:

Plugging this result back into Eq 2 we get .
A similar calculation gives the opposite change of dual basis:

Comparing this to Eq. 1, we see that the dual basis changes in the inverse manner as the basis.
For a vector , how do the vector components
change from the original to primed basis? Recall that
we can use the
'th dual basis to obtain the
'th component of a vector:

and similarly . Expanding
using Eq. 3:

So (after a similar calculation in the opposite direction) we see vector components change as:

Now consider a (1,1)-tensor with components
in the original basis. Unlike the book we use the
convention that a
-tensor
is a multilinear map:

How do the tensor components transform from the
original to primed basis? We can simply evaluate
on the primed basis and expand:
