Everything about Direct image functor
In mathematics, a mapping between categories
In mathematics, the direct image functor describes how structured data assigned to one space can be systematically transferred to another space using a continuous map between them. More precisely, if we have a sheaf—an object that encodes data like functions or sections over open regions—defined on a space X, and a continuous map from X to another space Y, then the direct image functor produces a corresponding sheaf on Y. This construction is a central tool in sheaf theory and is widely used in topology and algebraic geometry to relate local data across spaces. Wikipedia →
🧠Start here: a 6-step reading path
- Read the overview: Direct image functorA 5-minute orientation
- Pick up a classic book: Real World HaskellThe most-reprinted book on the subject
- Read the landmark paper: Locale morphisms with exact direct image functor in sheavesCited 1 times
- Go sideways: Fibred categoryA closely related topic
- Go sideways: Inverse image functorA closely related topic
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🗂️ The subject at a glance
🏆 Landmark papers (most cited)
đź“š Books worth reading
Real World HaskellBryan O'Sullivan, John Goerzen · 2008
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đź”— Related topics
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