I am working on a project, and I need to know the proof of this:
Any functor which preserves all colimits preserves epimorphisms.
So could you please tell me how or where I can find the proof for this corollary? Thank you very much.
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Sign up to join this communityI am working on a project, and I need to know the proof of this:
Any functor which preserves all colimits preserves epimorphisms.
So could you please tell me how or where I can find the proof for this corollary? Thank you very much.
This follows from the following fact. $e : X \to Y$ is an epimorphism if and only if
is a pushout. This should be very easy to verify. Pushouts are finite colimits and therefore if a functor preserves colimits it will map pushouts to pushouts and therefore epis to epis.