Hilbert’s fourteenth problem over finite fields, and a conjecture on the cone of curves
نویسنده
چکیده
Hilbert’s fourteenth problem asks whether the ring of invariants of any representation of a linear algebraic group is finitely generated over the base field. Nagata gave the first counterexample, using a representation of (Ga) 13, where Ga denotes the additive group [22]. In his example, the representation is defined over a field of large transcendence degree over the prime field (of any characteristic). Mukai simplified Nagata’s construction, showing that there are representations of (Ga) 3
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