Strict descent of powers of a nonzero proper ideal in a Noetherian domain
ID: strict-descent-of-powers-of-a-nonzero-proper-ideal-in-a-noetherian-domain
Let be a Noetherian ring that is an integral domain, and let be a nonzero proper ideal. If for some , the nonzero finitely generated module satisfies . Choose generators and write with . The adjugate matrix identity implies that annihilates . This determinant is for some , since every term except the constant term contains an entry from .
The determinant trick has thus supplied . A nonzero element of and multiplicative cancellation in an integral domain force , contradicting properness of . Therefore all positive powers of an ideal are distinct in this setting. Since they have the same radical of an ideal, there are infinitely many ideals with radical .
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