Dyadic notation

[moorepants]

I read a paper that used $\underline{I}$ for a dyadic. If I stick with $\bar{v}$ for vectors, then the underline makes for a better fit. The unit dyadic could still use a special symbol (analogous to $\hat{u}$).

I could also define $\hat{n}_{xx} = \hat{n}_x \otimes \hat{n}_x$ for shorter notation on unit dyadics, but maybe that is confusing because you would think it is a unit vector with a special subscript.

[Peter230655]

The book Dynamics... by Roithmayr and Hodges seems to use the 'underline' notation, with capital letters, see p76 ff of this book (otherwise, their introduction to dyadics did not impress me much).

[moorepants]

Do they use anything for a unit dyadic?

[Peter230655]

Yes, they call it $\underline{U}$, page 78 of this book.
You mean the dyadic, such that $v \cdot \underline{U} = \underline{U} \cdot v = v$ ?

[moorepants]

Ok, I was wondering if they had something different. I use hat for unit vectors, a different symbol than the bar for my vectors.

[moorepants]

I guess I could do $\hat{\underline{U}}$.

[Peter230655]

For vectors, they use boldface only, no superscripts.

[moorepants]

Yes, I'm aware of that. I can't write bold letters on the chalkboard, so I prefer to avoid it.