I really got stuck with the following contradiction.
Say we have a Moufang loop $Q$, $|Q| < \infty$.
To put it briefly, Moufang loops are groups that not necessary be associative, with extra identities. They are also quasigroups with neutral element.
- The classical loop solvability is equal to existence for loop $Q$ series $1 = A_0 \triangleleft A_1 \triangleleft\space ... \triangleleft\space A_n = Q$, $A_{i+1} / A_i$ - commutative group;
- There is a Feit-Thompson theorem which say that every finite group with odd order is solvable. In this work the theorem is proved for finite Moufang loops;
- Simple Moufang loop is a loop without nontrivial proper normal subloops. Finite simple nonassociative Moufang loops are called Paige loops;
There is a nice representation of Paige loops as a 3-generated loops. For Paige loops with odd order $q \neq 9$ the generators can be the following:
$\begin{pmatrix}1 & (1,0,0)\\\ (0,0,0) & 1\end{pmatrix}$, $\begin{pmatrix}1 & (0,1,0)\\\ (0,0,0) & 1\end{pmatrix}$, $\begin{pmatrix}0 & (0,0,u)\\\ (0,0,u^{-1}) & 1\end{pmatrix}$, where
$u$ - primitive element of $GF(q)$ (with $q$ elements);
Trivial check on commutativity of second and third generators by rule
$\begin{pmatrix}a & \alpha\\\ \beta & b\end{pmatrix} \begin{pmatrix}c & \gamma\\\ \delta & d\end{pmatrix} = \begin{pmatrix}ac+\alpha\delta & a\gamma+d\alpha-\beta\times\delta\\ c\beta+b\delta+\alpha\times\gamma & bd+\beta\gamma\end{pmatrix}$
Gives us that Paige loops are always noncommutative (generally regardless to the parity);
- Finally, by definition of solvability
$Q$ - simple finite solvable loop $\Rightarrow$ $Q$ - commutative (quotient of $Q$ by $1$).
Particularly by Feit-Thompson theorem, Paige loops with odd order are solvable, hence since they are simple, they must be commutative, but we showed that Paige loops are never commutative. A contradiction.
My question is: where the misfire is? What tricky moment I couldn't see here?
According to https://groupprops.subwiki.org/wiki/Paige_loop, the order of a Paige loop is $q^3(q^4-1)$ when $q$ is even and $\frac{1}{2}q^3(q^4-1)$ when $q$ is odd. Hence a Paige loop can never have odd order.