Using Tensor double dots in Latex, with tensor package

Question

I am currently struggling to find a way to write :

I know of \cdots and \cdot but the output is one dot and 3 dots but not two. What is a possible solution to my problem?

Thanks in advance.

Answer 1

You can define your own symbol; since it is a binary operation, use \mathbin; the \cdot symbol can then be repeated twice.

\documentclass{article}
\usepackage{amsmath}
\usepackage{lmodern}

\DeclareMathAlphabet{\mathsfbfsl}{OT1}{\sfdefault}{bx}{sl} % for boldface slanted sans serif

\newcommand{\vct}[1]{\mathbf{#1}}
\newcommand{\tns}[1]{\mathsfbfsl{#1}}
\newcommand{\cddot}{\mathbin{{\cdot}{\cdot}}}

\begin{document}

$\vct{T}=\tns{C}\cddot\vct{E}$

\end{document}