Quick one. If I'm not mistaken, the columns of a character table represent the conjugacy class associated with a group. When we talk of the "rational classes" of the group, is this related to the entries of the columns of the character table being rational ($\in \mathbb{Q}$)?
The reason why I ask this is because this document here: (http://www.math.colostate.edu/~hulpke/lectures/666/hw10.pdf) says that the conjugacy classes 2A, 4A, 11A (in ATLAS notation) are rational classes (see q40). But if one is to look at the character table of M11 (simply using GAP) we see that the columns of 11A are not rational? Perhaps I am mistaken.
Thank you for your help.
In GAP, a "rational class consists of all elements that are conjugate to g or to an i-th power of g where i is coprime to the order of g. Thus a rational class can be interpreted as a conjugacy class of cyclic subgroups."
See https://www.gap-system.org/Manuals/doc/ref/chap39.html#X8733F87B7E4C9903
UPDATE: In an earlier version of this answer, I made the incorrect claim that this has nothing to do with character theory. Thankfully, Derek Holt pointed out my mistake in a comment below.