Potential good reduction

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In mathematics, potential good reduction is a property of the reduction modulo a prime or, more generally, prime ideal, of an algebraic variety.

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Definitions

Good reduction refers to the reduced variety having the same properties as the original, for example, an algebraic curve having the same genus, or a smooth variety remaining smooth. Potential good reduction refers to the situation over a sufficiently large finite extension of the field of definition.

Equivalent formulations

For elliptic curves, potential good reduction is equivalent to the j-invariant being an algebraic integer.

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