Spectrum functor converts direct limits to inverse limits
Statement
Category-theoretic statement
The natural map from the spectrum of the direct limit of a directed system of commutative unital rings, to the inverse limit of their spectra, is an isomorphism.
Verbal statement
Suppose is a directed set and is a directed system of commutative unital rings indexed by . Suppose is the direct limit of the s. Then the natural map:
is an isomorphism.