Index

Commutative algebra is a branch of algebra that studies commutative rings, their ideals, and modules over such rings. It provides the algebraic foundation for algebraic geometry and number theory.

Topics Covered

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Affine Algbraic Varieties

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Tips

  1. How to instantiate a typeclass?

    Take CoeOut as an example :

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Index

Notes from learning Lean and the Mathlib library.

Mathematics in Lean

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Index

This section will collect learning notes on cryptographic primitives, protocols, and the mathematics behind their security.

Planned topics

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Index

Planned topics (notes not yet published):

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Cryptographic Functions

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Closest Vector Problem

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Basic Reduction Problem

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Structures

Table of Contents

Table of Contents


Invariant Subspaces

Definition 5.1 – Invariant Subspace

Let $T \in \mathcal{L}(V)$ be a (linear) operator on vector space $V$. When we restrict $T$ to a subspace $U \subseteq V$, we are not sure the corresponding vectors will still lie in $U$. If they do, we say that $U$ is an invariant subspace under $T$. We call $T|_U$ is an operator on $U$.

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