Yoneda lemma

Summary

Yoneda lemma is a theorem^[1]. It ranks in the top 3% of theorem entities by monthly Wikipedia readership (770 views/month).^[2]

Key Facts

• Yoneda lemma's instance of is recorded as theorem^[3].
• Nobuo Yoneda is named after Yoneda lemma^[4].
• Yoneda lemma's Freebase ID is recorded as /m/088bx^[5].
• Yoneda lemma's defining formula is recorded as \begin{aligned}\hom_{\operatorname{PSh}(C)}(\hom_C(-,c),X)&\cong X(c)&(X&\in\operatorname{PSh}(C))\\hom_{\operatorname{PSh}(C^{\operatorname{op}})}(\hom_C(c,-),X)&\cong X(c)&(X&\in\operatorname{PSh}(C^{\operatorname{op}}))\end{aligned}^[6].
• Yoneda lemma's studied by is recorded as category theory^[7].
• Yoneda lemma's nLab ID is recorded as Yoneda lemma^[8].
• Yoneda lemma's schematic is recorded as Yoneda lemma cd.svg^[9].
• Yoneda lemma's maintained by WikiProject is recorded as WikiProject Mathematics^[10].
• Yoneda lemma's Microsoft Academic ID is recorded as 2780771819^[11].
• Yoneda lemma's ProofWiki ID is recorded as Yoneda_Lemma^[12].
• Yoneda lemma's in defining formula is recorded as \operatorname{PSh}(C)^[13].
• Yoneda lemma's in defining formula is recorded as \hom_{\operatorname{Psh}(C)}^[14].
• Yoneda lemma's in defining formula is recorded as C^[15].

Why It Matters

Yoneda lemma ranks in the top 3% of theorem entities by monthly Wikipedia readership (770 views/month).^[2] It has Wikipedia articles in 15 language editions, a strong signal of global cultural recognition.^[16]