Why Linear Algebra Matters for AI
3 entriesAlmost everything a modern AI system computes is linear algebra. Data are stored as vectors, matrices and tensors; a neural-network layer is a matrix multiplication followed by a nonlinearity; word and image embeddings are vectors compared by dot products or cosine similarity; and transformer attention is a sequence of matrix products. Decompositions such as SVD and eigendecomposition power PCA, recommender systems and model compression, while low-rank updates make fine-tuning large models affordable. GPUs and libraries such as BLAS exist largely to make matrix multiplication fast. This page collects free books, courses, papers and tools for each area.
Foundations & Learning Resources
11 entriesCore ideas and where to learn them.
Matrix Decompositions & Dimensionality Reduction
9 entriesFactorizations that reveal structure in data.
Linear Algebra Inside Neural Networks
9 entriesWhere matrices and tensors appear in models.
Low-Rank Methods & Efficient AI
7 entriesUsing structure in matrices to cut cost.
Numerical Linear Algebra & Hardware
8 entriesComputing with matrices accurately and fast.
Libraries & Tools
9 entriesSoftware for linear algebra in Python, Julia and more.
Related Pages
10 entriesNeighbouring pages on this site.
Frequently Asked Questions
Why is linear algebra important for AI?
Data, model parameters and activations are stored as vectors, matrices and tensors, and training and inference are dominated by matrix multiplication. Understanding linear algebra explains embeddings, attention, dimensionality reduction and why GPUs speed up deep learning.
Which linear algebra topics should I learn first for machine learning?
Vectors and dot products, matrices and matrix multiplication, linear systems, eigenvalues and eigenvectors, and the singular value decomposition. Then add norms, orthogonality, projections and matrix calculus for understanding gradients.
How is linear algebra used in transformers and LLMs?
Token embeddings are vectors; attention projects them with learned weight matrices into queries, keys and values, scores them with matrix products and a softmax, and mixes the values. Feed-forward layers are further matrix multiplications.
What is LoRA and how does it relate to linear algebra?
LoRA fine-tunes a large model by freezing the original weights and learning a low-rank update, the product of two small matrices. It relies on the idea that useful weight changes can be well approximated by a matrix of low rank.
What is the difference between SVD and PCA?
PCA finds the directions of greatest variance in centred data and can be computed from the SVD of the data matrix. SVD is the more general factorization and also applies to matrices that are not centred or are not data tables.
How current is this page?
Links were checked in October 2026. This is an introductory map, not a textbook: it points to free books, courses, papers and libraries. Sites that block automated checks are kept and may need a manual click.