New posts in Root Systems

How do I use the fact that $\langle \gamma, \lambda \rangle > 0$?

How to prove that $B^\vee$ is a base for coroots?

Length of root strings is at most 4

Number of reduced decompositions of the longest element of the Weyl group

Non-faithful irreducible representations of simple Lie groups

Where does the really nice '8-dimensional' description of the $E_7$ root system come from?

Significance of half-sum of positive roots belonging to root lattice?

References about Hasse diagrams of root systems