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Ideals modulo a prime. (English) Zbl 1472.13043
The present paper deals with the problem of reducing an ideal modulo $$p$$, i.e. relating an ideal $$I$$ in the polynomial ring $$\mathbb{Q}[x_1,\dots,x_n]$$ to a corresponding ideal in $$\mathbb{F}_p[x_1,\dots,x_n]$$ where $$p$$ is a prime number.
The authors define a notion of $$\sigma$$-good prime, where $$\sigma$$ is a term ordering and relate it to other similar notions in the literature. Furthermore, the paper introduces a new invariant called universal denominator, which is independent of the term ordering and allows to show that all but finitely many primes are good for $$I$$ (see Definiton 2.4).
The methods in the paper make it easy to detect bad primes, a key feature in modular methods (Theorem 4.1 and Corollary 4.2).
The paper includes practical applications to modular computations of Gröbner bases and also includes examples of computations using the computer algebra systems CoCoA and SINGULAR.
##### MSC:
 13P10 Gröbner bases; other bases for ideals and modules (e.g., Janet and border bases) 13P25 Applications of commutative algebra (e.g., to statistics, control theory, optimization, etc.) 13-04 Software, source code, etc. for problems pertaining to commutative algebra 14Q10 Computational aspects of algebraic surfaces 68W30 Symbolic computation and algebraic computation
##### Keywords:
ideals; modular; Gröbner bases; term orderings
##### Software:
CoCoALib; gmp; CoCoA; SINGULAR
Full Text:
##### References:
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