How statement and proof provenance work
The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.
- Literature-sourced: the exact statement appears in a cited source; only wording and notation differ.
- AI-adapted: a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
- AI-generated: a genuinely novel statement formulated by AI, with no source for the claim itself.
These labels describe origin, not correctness: citations and verification chips remain separate evidence.
Polynomials that split and splitting fields of a polynomial or a family of polynomials
Definition
Let be a field extension and let have degree . The polynomial splits over if there are and such that in , with repetitions allowed. When , the product is empty, so every nonzero constant polynomial splits over .
For a family of nonzero polynomials in , a splitting field of over is a field extension such that every member of splits over and is generated over by all roots in of all polynomials in . A splitting field of the one-element family is called a splitting field of . For the empty family, the set of roots is empty and its splitting field is .
Depends on
Used by
- Every finite family of nonzero polynomials has a splitting field, obtained from their product Corollary
- Inside a common extension, the splitting field of fg is the composite of the splitting fields of f and g Corollary
- A normal algebraic extension is one in which every minimal polynomial with a root in the extension splits there Definition
- Over F₂, x⁴+x²+1=(x²+x+1)² has two distinct roots, each repeated, in its four-element splitting field Example
- The base field is the splitting field of the empty family and of every nonzero constant polynomial Example
- The splitting field of {x²-2,x²-3} over ℚ is ℚ(√2,√3) Example
- The splitting field of x²-2 over ℚ is ℚ(√2), with roots ±√2 Example
- The splitting field of x⁴+2x²-8 over ℚ is ℚ(√2,i) Example
- A field isomorphism transports polynomials coefficientwise and carries roots, factorizations, and splitting to roots, factorizations, and splitting Lemma
- Kronecker's one-root step: adjoining a root removes a linear factor and lowers the remaining degree Lemma
- A normal extension generated by finitely many elements is the splitting field of the product of their minimal polynomials Proposition
- After adjoining one nonzero root α of xⁿ-a, all roots are ζα with ζⁿ=1 Proposition
- An algebraic extension that is a splitting field of a polynomial is normal Proposition
- Every F-endomorphism of a splitting field permutes the distinct roots and is an automorphism Proposition
- A base-field isomorphism extends to an isomorphism between splitting fields of corresponding polynomials Theorem
- A degree-n polynomial has a splitting field spanned over F by at most n! explicit root monomials Theorem
- An algebraic extension generated by elements whose minimal polynomials split in it is normal Theorem
- Every nonzero polynomial over a field has a splitting field Theorem
Dependency tree · next 3 levels
Direct dependencies and their dependencies through the next three levels: 23 results over 9 levels. An arrow runs from a result to what uses it, and this result sits at the bottom with a heavier outline. Click the chart to enlarge it.
Sources
- T. Judson, Abstract Algebra: Theory and Applications, Section 21.2 (standard reference, not scraped)
- J. S. Milne, Fields and Galois Theory, Chapter 2 (standard reference, not scraped)