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Mathematics,
Algorithms & AI.
Notes on the questions in mathematics, algorithms and AI that are worth understanding more than once: what structure a result depends on, why a method works, and under what conditions it fails.
Structure/Mechanism/Boundary
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Est. 2025Mathematics · Algorithms · AIShanghai
STRUCTURE
Mathematics clarifies structure
Find, among definitions, assumptions and derivations, the part that actually decides the result.
MECHANISM
Algorithms explain process
Follow invariants, information flow and computational steps instead of only stating the outcome.
BOUNDARY
Verification marks the boundary
Use counterexamples, experiments and sources to show when a claim holds and when it breaks.
Latest
Latest notes
Learning TheoryFoundation
Littlestone Dimension
Littlestone dimension, the optimal mistake bound, and the SOA proof, with a comparison to VC dimension.
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Reinforcement LearningMechanism
Policy Gradient from an Optimization Viewpoint
One continuous line from the objective to gradient estimation, variance and stepsize choice.
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Deep LearningPaper Reading
LeWorldModel / SIGReg: Why Doesn't It Collapse?
Connecting latent prediction, representation collapse and SIGReg, and identifying the conditions the mechanism actually depends on.
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Information TheoryDerivation
Typical Sets: Where Probability Mass Lives in High Dimensions
Why does probability mass sit on a thin shell rather than at the point of highest density?
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Knowledge map
Knowledge map
Keya coloured region is a subject; concepts where regions overlap belong to each of thembeads on a card: the subjects it belongs torelations appear when you point at or select a concept9 of 13 concepts span more than one subject
NodesConceptTheoremMethodModelPaperwrittenplannedSelect a subject name to open its map; select a concept to read about it4 / 13 written
Select a subject name to open its map; select a concept to read about it4 / 13 written
Probability1/4
Statistics0/2
Information Theory1/4
Optimization1/3
Reinforcement Learning1/3
Deep Learning3/5
Generative Models0/5
Select a node to see its summary and how it relates to the others.