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.
The quotient group and coset product
Definition
Let be a group and let be a normal subgroup (Normal subgroup: invariance under conjugation). The quotient group, or factor group, has the left cosets
as its elements (Left and right cosets and of a subgroup, The coset set and the index of a subgroup), with product
Independence of the chosen representatives is proved in Coset multiplication is well defined if and only if is normal ↗, and the group axioms are proved in For , the cosets form a group with identity and inverse ↗.
Depends on
Used by
- An extraspecial p-group has order p¹⁺²ⁿ for some n≥1 Corollary
- An extraspecial p-group is the product of two maximal abelian subgroups meeting in its centre Corollary
- Converse of Lagrange for finite abelian groups: every divisor occurs as a subgroup order Corollary
- If one set in a van Kampen cover is simply connected, the other fundamental group surjects with overlap-generated kernel Corollary
- The centre of an extraspecial p-group has no complement Corollary
- 1→⟨ i⟩→ Q₈→ Q₈/⟨ i⟩→1 does not split, with nonabelian middle group Counterexample
- An HNN extension with its stable letter Definition
- Group presentation by generators and relations Definition
- Quotient module M/N with scalar multiplication on additive cosets Definition
- Supersolvable groups and monomial characters Definition
- The abelianisation Gᵃᵇ:=G/[G,G] and its canonical map Definition
- The central product G∘_α H of two groups along an isomorphism of central subgroups Definition
- The commutator pairing of an extraspecial p-group relative to a chosen generator of its centre Definition
- The outer automorphism group Out(G)=Aut(G)/Inn(G) Definition
- The profinite completion is the inverse limit of the finite quotients G over N Definition
- The quotient ring R/I with (r+I)(s+I)=rs+I Definition
- The square map of an extraspecial 2-group relative to a chosen generator of its centre Definition
- The tensor product M⊗_R N from the additive group underlying the free ℤ-module on M× N, elementary tensors, and finite tensor sums Definition
- The upper central series Definition
- A nonabelian supersolvable group has a noncentral normal abelian subgroup Lemma
- A nontrivial finite abelian p-group with a unique subgroup of order p is cyclic Lemma
- A product formula for the number of square roots of the identity in a central product of extraspecial 2-groups Lemma
- A subgroup of the central quotient and its orthogonal complement have orders multiplying to the order of the quotient Lemma
- Central factors are equivalent to adjacent commutator containments Lemma
- Elementary groups are supersolvable Lemma
- Every finite abelian group is a quotient of (ℤ/n)ᵏ for some n and k Lemma
- If G/Z(G) is cyclic, then G is abelian Lemma
- If K is normal in G, N is normal in G and K⊆ N, then N/K is normal in G/K Lemma
- Monomiality lifts along a quotient Lemma
- The commutator pairing is well defined on the central quotient, is bilinear over Fₚ, and is alternating Lemma
- The commutator pairing of an extraspecial p-group has trivial radical Lemma
- The kernels of the finite coordinate projections form an open normal neighbourhood basis at the identity Lemma
- The square map is well defined on the central quotient and satisfies q(x̄ȳ)=q(x̄)+q(ȳ)+b(x̄,ȳ) Lemma
- The successive quotients pⁱG/pⁱ⁺¹G recover the cyclic summand multiplicities of a finite abelian p-group Lemma
- The transitive subgroups of S₄ and their action on the three pairings Lemma
- Two elements of an extraspecial p-group with nontrivial commutator generate an extraspecial subgroup of order p³ Lemma
- Abelian groups and ℤ-modules have the same objects and morphisms Proposition
- Dih(C₄) and Q₈ are extraspecial of order 8, with six and two solutions of x²=1 respectively Proposition
- Every intermediate field of ℚ(μₙ)/ℚ is Galois over ℚ with abelian Galois group Proposition
- In ⟨ X∣ R⟩, the words u and v represent the same element if and only if u⁻¹v∈⟨⟨ R⟩⟩ Proposition
…and 28 more results.
Dependency tree · two levels
8 results within two dependency steps of this one, each drawn at its shortest distance from it. An arrow runs from a result to what uses it, so the chart reads left to right and ends at this result, which carries a heavier outline. Every node is a link to that result. Click elsewhere on the chart to enlarge it.
Sources
- T. W. Judson, Abstract Algebra: Theory and Applications, Factor Groups and Normal Subgroups (standard reference, not scraped)