It is known that the intersectionnintersection of kernels of all ireductibileireducible representations of a finite group in charcteristiccharacteristic zero is the trivial group.
In caracteristic pcharacteristic $p>0$ I have understood that this intersection îs $O_p(G)$, the largest normal p $p$ - subgroup of G$G$. In other words, all irreducible represntationsrepresentations of G are coming from the quotient $G/O_p(G)$.
I have some dificulties to proovedifficulties in proving this similar result in characteristic p$p$ dividing the order of G$G$. Could Simeone please givesomeone provide me with a reference for this result? Or shortly explain the argument to me. My intuition is that this is not so difficult.