arXiv subjects
Publications and source records attributed to Valerio Guido.
Six fine gradings on the real form $\mathfrak{e}_{6,-14}$ are described, precisely those ones coming from fine gradings on the complexified algebra. The universal grading groups are $\mathbb Z_2^3\times\mathbb Z_3^2$, $\mathbb Z_2^6$, $\mathbb Z\times\mathbb Z_2^4$, $\mathbb Z_2^7$, $\mathbb Z\times\mathbb Z_2^5$ and $\mathbb Z^2\times\mathbb Z_2^3$.
We describe four fine gradings on the real form $\mathfrak e_{6,-26}$. They are precisely the gradings whose complexifications are fine gradings on the complexified algebra $\mathfrak{e}_6$. The universal grading groups are $\mathbb Z_2^6$, $\mathbb Z\times\mathbb Z_2^4$, $\mathbb Z^2\times\mathbb Z_2^3$, and $\mathbb Z_4\times\mathbb Z_2^4$.
Satake diagrams of the real forms $ \mathfrak{e}_{6,-26}$, $ \mathfrak{e}_{6,-14}$ and $ \mathfrak{e}_{6,2}$ are carefully developed. The first real form is constructed with an Albert algebra and the other ones by using the two paraoctonion algebras and certain symmetric construction of the magic square.
The Weyl groups of the fine gradings with infinite universal grading group on $\mathfrak{e}_6$ are given.