So, I have studying an article about modeling a noise in my study field (Telecomunications) and I have found a mathematical notation that I never had found before.
$\overrightarrow W(t) \sim N(\vec 0, tI)$
followed by the expression:
$\overrightarrow W(t) = [W_1,...,W_n]^T$
in the article, the author explicitates that $n = 12$, but not especificate $I$. I don't know if this $I$ is part of notation of a Wiener process or something else. In really, I don't know how to interpretate the notation of the Wiener process, in a first moment, i have thinked that's was a simple normal distribuction, but in my research on web, I'd realize that's more complicated.