English
The forgetful functor from commutative groups to groups is fully faithful.
Русский
Забывающий функтор из коммутативных групп в группы полно и полнообразен (полносвязный и полнофидный).
LaTeX
$$$$ (\text{forget}_{\mathrm{CommGrpCat},\mathrm{GrpCat}}) \, \text{ is fully faithful}. $$$$
Lean4
/-- The forgetful functor from commutative groups to groups is fully faithful. -/
@[to_additive fullyFaihtfulForget₂ToAddGrp /--
The forgetful functor from additive commutative groups to additive groups is fully faithful. -/
]
def fullyFaithfulForget₂ToGrp : (forget₂ CommGrpCat.{u} GrpCat).FullyFaithful where preimage f := ofHom f.hom