Irreducible polynomials and prime elements

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SUMMARY

The discussion centers on the relationship between prime elements in the ring Z[√3] and the irreducibility of the polynomial x²−3 in the polynomial ring Fp[x]. It is established that a prime p in Z is a prime element of Z[√3] if and only if x²−3 is irreducible in Fp[x]. The irreducibility of the polynomial ensures that the quotient ring Zp[x]/(x²−3) forms an integral domain, confirming the prime status of p. Additionally, the conversation touches on the distinction between integral domains and fields, particularly regarding ideals generated by irreducible polynomials.

PREREQUISITES
  • Understanding of prime elements in ring theory
  • Familiarity with polynomial irreducibility in finite fields
  • Knowledge of integral domains and field theory
  • Basic concepts of ideal theory in algebra
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  • Study the properties of irreducible polynomials in finite fields
  • Learn about the structure of integral domains and fields
  • Explore the concept of maximal ideals in ring theory
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Mathematicians, algebraists, and students studying abstract algebra, particularly those interested in ring theory and polynomial irreducibility.

darksidemath
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How can I show that p is a prime element of Z[√3]?
let p∈Z a prime how can I show that p is a prime element of Z[√3] if and only if the polynomial x^2−3 is irreducible in Fp[x]? ideas or everything is well accepted :)
 
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If ##p\in R## is prime, then ##R/(p)## is an integral domain.

If ##x^2-3\in \mathbb{Z}_p[x]## is irreducible, then ##\mathbb{Z}_p[x]/(x^2-3)\cong \mathbb{Z}_p[\sqrt{3}]\cong \mathbb{Z}[\sqrt{3}]/(p)## is an integral domain.
 
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fresh_42 said:
If ##p\in R## is prime, then ##R/(p)## is an integral domain.

If ##x^2-3\in \mathbb{Z}_p[x]## is irreducible, then ##\mathbb{Z}_p[x]/(x^2-3)\cong \mathbb{Z}_p[\sqrt{3}]\cong \mathbb{Z}[\sqrt{3}]/(p)## is an integral domain.
I thought the quotient by the ideal generated by an irreducible is a field, not just an integral domain.
 
It's a field if the ideal is maximal. There are no problems in principal ideal domains, but the general case is more complicated.
 
Aren't ideals generated by irreducible polynomials maximal?
 
WWGD said:
Aren't ideals generated by irreducible polynomials maximal?
I'm not sure and have been too lazy to think about it. E.g. we could have a situation ##(p) \subsetneq (p,q) \subsetneq R.##
 

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