ABSTRACT
Let k be an algebraically closed field of characteristic two and let 𝔾a be the additive group of k. Given any non-trivial representation ρ:𝔾a→GL(4,k), we let 𝔾a act linearly, via ρ, on the polynomial ring in four variables over k. Then we prove that the invariant ring is isomorphic to the polynomial ring in three variables over k.
2010 MATHEMATICS SUBJECT CLASSIFICATION:
Acknowledgment
The author would like to express his gratitude to the referee for comments.