MHB Solving for $F(v,f)$ in Tensor $F$

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The discussion revolves around calculating the value of the tensor $F(v,f)$, where $F$ is defined as $F=e^1\otimes e_2 + e^2\otimes(e_1+3e_3)$. The participants clarify that $e^1\otimes e_2$ does not equal zero, as it corresponds to a non-zero matrix $E_{12}$. This matrix representation is essential for understanding the tensor's action on vectors and covectors. The computation involves evaluating the expression using the defined vectors $v$ and $f$. Overall, the conversation emphasizes the importance of tensor representation in linear algebra.
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Hello everyone

Here is the problem:

Find the value $F(v,f)$ of the tensor $F=e^1\otimes e_2 +e^2\otimes(e_1+3e_3)\in T^1_1(V)$ where $v=e_1+5e_2+4e_3, f=e^1+e^2+e^3$

Does $e^1\otimes e_2=0$ in this problem?Thanks
 
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I wouldn't think so, it seems to me that $e^1 \otimes e_2$ corresponds to the matrix:

$E_{12} = \begin{bmatrix}0&1&0\\0&0&0\\0&0&0 \end{bmatrix}$

which is not the 0-matrix.

That is, that:

$e^i \otimes e_j (v,u^{\ast}) = u^TE_{ij}v $, a scalar in the underlying field.
 
Deveno said:
I wouldn't think so, it seems to me that $e^1 \otimes e_2$ corresponds to the matrix:

$E_{12} = \begin{bmatrix}0&1&0\\0&0&0\\0&0&0 \end{bmatrix}$

which is not the 0-matrix.

That is, that:

$e^i \otimes e_j (v,u^{\ast}) = u^TE_{ij}v $, a scalar in the underlying field.

Got it, thanks a lot:)
 
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