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Results tagged with invariant-theory
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user 17734
Invariant theory deals with an algebraic, geometric or analytic structure $X$, submitted to the action of an (algebraic) group $G$. It studies $G$-invariant elements of $X$ as well as the set of $G$-orbits.
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Is the restriction of a graded automorphism of a polynomial ring to a polynomial subring lin...
No. Counterexample: Let $\deg x = \deg y = 1$ and take
$$A=\mathbb{F}_2[x,y],\,\,\,B=\mathbb{F}_2[x,y^2],\,\,\,\,\,g(x)=x,\,\,g(y)=x+y$$
As already observed by the OP, since the generators of $B$ hav …
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