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Every man is like the company he is wont to keep.Euripides | Universal Properties III - Yoneda's Lemma
Recently updated notes
| Note | Last Updated | 
|---|---|
| Algebras | 2:03 PM - October 30, 2025 | 
| Exact Sequences IV - Exact Sequences and Functors | 1:59 PM - October 30, 2025 | 
| 2025-10-30 | 1:53 PM - October 30, 2025 | 
Knowledge
Mathematics
 Algebra theory
Not to be confused with the general concept of algebra (abstract or otherwise), an algebra is an algebraic structure similar to a module, only with two internal binary operations.
| Note | Last Updated | 
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| Algebras | 2:03 PM - October 30, 2025 | 
| Exterior algebras | 7:22 AM - March 31, 2025 | 
| Symmetric algebras | 7:23 AM - March 31, 2025 | 
| Symmetric and alternating tensors | 7:23 AM - March 31, 2025 | 
| Tensor algebras | 6:54 AM - October 30, 2025 | 
 Algebraic geometry
| Note | Last Updated | 
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| Examples of classical conic duality | 7:24 AM - March 31, 2025 | 
 Category theory
| Note | Last Updated | 
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| Abelian categories | 12:33 PM - March 31, 2025 | 
| Additive categories | 12:34 PM - March 31, 2025 | 
| Adjoints | 8:45 PM - October 07, 2025 | 
| Categories | 7:55 PM - October 07, 2025 | 
| Chain complexes | 12:34 PM - March 31, 2025 | 
| Diagram chases without elements | 7:26 PM - November 23, 2024 | 
| Diagram lemmas | 12:34 PM - March 31, 2025 | 
| Double complexes and mural maps | 12:35 PM - March 31, 2025 | 
| Exact sequences and chain homology | 12:35 PM - March 31, 2025 | 
| Examples of adjoints | 9:00 PM - October 07, 2025 | 
| Functor categories | 8:42 PM - October 07, 2025 | 
| Functors | 8:12 PM - October 07, 2025 | 
| Natural transformations | 8:38 PM - October 07, 2025 | 
| Preadditive categories | 12:36 PM - March 31, 2025 | 
| Properties of adjoints | 12:39 PM - March 31, 2025 | 
| Special morphisms | 12:47 PM - March 31, 2025 | 
| Spectral sequences | 12:37 PM - March 31, 2025 | 
| The Salamander Lemma | 12:37 PM - March 31, 2025 | 
| Universal arrows and elements | 12:48 PM - March 31, 2025 | 
| Universal Properties I - Inspiring Examples | 7:56 PM - October 07, 2025 | 
| Universal Properties II - Commutative diagrams, cones and limits | 3:08 PM - August 06, 2025 | 
| Universal Properties III - Yoneda's Lemma | 10:14 AM - October 17, 2025 | 
 Differential equations
 Field theory
| Note | Last Updated | 
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| A question about finite fields | 10:26 AM - May 30, 2025 | 
 Group theory
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| Normal subgroups | 7:25 AM - March 31, 2025 | 
 Module theory
 Representation theory
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| Representations of groups | 9:26 AM - July 08, 2025 | 
 Ring theory
| Note | Last Updated | 
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| Chinese Remainder Theorem | 9:26 AM - July 15, 2025 | 
| Division rings | 9:54 AM - July 15, 2025 | 
| Graded rings | 7:25 AM - March 31, 2025 | 
| Least common multiples | 7:34 PM - July 21, 2024 | 
| Principal ideal domains (PIDs) | 6:29 AM - May 07, 2024 | 
 Tropical algebraic geometry
| Note | Last Updated | 
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| Investigation into tropical tangency loci | 7:27 AM - March 31, 2025 | 
| Linear tropical varieties | 7:27 AM - March 31, 2025 | 
| Quadratic tropical varieties | 7:27 AM - March 31, 2025 | 
| Tropical varieties | 7:27 AM - March 31, 2025 | 
Software
 Blender
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 Houdini
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| Systems of equations | 2:56 PM - August 06, 2024 |