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.
Realification of a complex vector space by restriction of scalars
Definition
Let be a vector space over the field (The complex numbers as , with the real embedding and imaginary unit ). Its realification, written , is the real vector space whose underlying set and addition are those of , and whose scalar multiplication is the restriction of the complex scalar multiplication to the canonical real embedding :
The axioms of a real vector space are the restriction of the corresponding complex axioms: complex scalar multiplication is already an -scalar multiplication, since is a subfield of through the constant-class map of The complex numbers as , with the real embedding and imaginary unit .
Remarks
Realification forgets the chosen complex structure: different complex structures on the same abelian group can have the same realification. The definition is the prototype of restriction of scalars along ; no basis and no choice of coordinates is involved.