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📄 2026-10-21 · Paper walkthroughs Paper Explained: Refusal in Language Models Is Mediated by a Single Direction — saying "no" lives on one line inside the model When chat models turn down harmful requests, that behavior is Paper Deep-Dives · ★ ◆ 2026-10-13 What Ratio Should the Validation Split Be — I Swept It, and What Mattered Was the Count, Not the Ratio When you split your data into training and validation, is it 8 Machine Learning Basics ◆ 2026-09-27 Dark Silicon — You Can Place the Transistors, You Just Can't Light Them All The number of transistors you can put on a chip keeps rising, Scaling & Power ◆ 2026-09-23 · Paper walkthroughs The Fourier Transform from Scratch — Reading a Signal as a Stack of Pure Tones A signal drawn against time hides the thing you usually want t Numerical Computing 🎲 2026-09-23 · Paper walkthroughs Bayes' Theorem from Scratch — Why a 99% Accurate Test Can Be a Coin Flip Bayes' theorem is four symbols that reverse a conditional prob Probability & Statistics ◆ 2026-08-27 LDPC and Turbo Codes — The Error Correction Behind 5G and Deep Space Shannon proved in 1948 that these codes exist, and nobody coul Coding Theory · ★ 🔐 2026-09-23 · Paper walkthroughs RSA from Scratch — The Number Theory Behind Public Keys RSA lets you publish a key that locks but cannot unlock. This Security ◆ 2026-10-21 · Paper walkthroughs Paper Explained: Holi-World — Turning First-Person Recordings into a Ledger of the Room, Then Teaching a VLM to Reason over It Holi-World (arXiv:2610.26549) automatically turns first-person Time Series · ★ 🏭 2026-08-29 Mapping the Semiconductor Supply Chain — From Sand to Chip, Who Holds What One pass through the whole chain that makes a chip — design (E Supply Chain ◆ 2026-08-27 Solving Systems of Equations — Direct Methods and Iterative Methods How much a bridge sags, how heat spreads through a room, what Numerical Computing · ★ 📐 2026-09-13 · Paper walkthroughs PCA from Scratch — Eigenvectors as the Axes of Your Data A cloud of correlated data has a grain — a direction along whi Linear Algebra ◆ 2026-08-25 HLS and DASH — How Video Actually Reaches You Streamed video does not flow — a player downloads small files Media in Production ◆ 2026-08-29 Upstream Engineering from Scratch — Why Projects Are Won or Lost at Requirements Requirements, then high-level design, then detailed design — w Engineering Process ◆ 2026-10-20 · Paper walkthroughs Dynamic Band Splitting — Letting Each Mixture Decide Where the Frequency Bands Go Band-split source separators carve the spectrum into hand-desi Audio & Speech · ★ ◆ 2026-09-06 RAG vs Fine-Tuning — Which One, and When The two main ways to make an LLM better, compared on four axes RAG & Retrieval 🏭 2026-08-29 Upstream of Semiconductors — Wafers, Photoresist, and Specialty Gases How sand becomes silicon that is 99.999999999% pure, gets pull Supply Chain ◆ 2026-08-27 Concurrency from Scratch — Locks, Atomics, and Memory Models Why data races happen and why they refuse to reproduce in your Parallel & Distributed · ★ ◆ 2026-09-13 · Paper walkthroughs Gradient Descent from Scratch — The Geometry of Learning Every model that learns is walking downhill on a surface it ca Calculus & Optimization ◆ 2026-08-25 · Paper walkthroughs Why Opus Won — The Design of a Modern Audio Codec Audio codecs used to split cleanly into speech codecs and musi Audio Codecs · ★ ◆ 2026-08-29 The Craft of Requirements — Why "We Built Exactly What They Asked For" Fails Why shipping precisely what a stakeholder asked for produces s Engineering Process 🏋 2026-10-12 · Paper walkthroughs Transformers Stop Thinking Too Early — How a One-Layer Rank-8 LoRA Stretches 3-Line Reference Following to 50 Pretrained LLMs follow in-context variable references for only Training & Alignment · ★ 🏭 2026-08-29 Inside the Equipment Makers — What ASML, AMAT, TEL and Lam Actually Build Chip manufacturing is four actions repeated hundreds of times Supply Chain · ★ ◆ 2026-08-27 Build Your Own Autograd — A Mini PyTorch in 100 Lines Start from a single Value class, add operator overloading, top Numerical Computing · ★ 🎲 2026-08-27 · Paper walkthroughs Statistical Learning Theory — Why Does Learning Generalize? You only ever see finitely many examples, yet the model answer Probability & Statistics · ★ ◆ 2026-08-25 · Paper walkthroughs Neural Compression — The Codec That Learns JPEG's quantization table and H.264's prediction modes were ta Video Codecs · ★ ◆ 2026-08-29 Estimation and Scope — The Cone of Uncertainty and How to Negotiate Estimates miss because a question about a range gets answered Engineering Process · ★ 📄 2026-10-11 · Paper walkthroughs From Evidence to Action: How Tool-Using Agents Fail — Reading the Failure Diagnostics and Interventions SafeActBench splits tool-using agent failures into a chain of Paper Deep-Dives · ★ 🏭 2026-08-29 IP Cores and the Fabless Model — How Arm Rules Silicon Without Making a Single Chip Why a company that only sells blueprints ends up at the center Supply Chain · ★ ◆ 2026-08-26 · Paper walkthroughs Probabilistic Data Structures — Counting Without Counting Bloom filters, HyperLogLog and the Count-Min sketch explained Data Structures · ★ 🎲 2026-08-27 · Paper walkthroughs Optimal Transport — The Mathematics of Moving Distributions Optimal transport measures the distance between two probabilit Probability & Statistics · ★ ◆ 2026-08-25 · Paper walkthroughs Neural Audio Codecs — EnCodec and the Foundation Under Speech LLMs MP3 and Opus were hand-designed around what the ear cannot hea Audio Codecs · ★ ◆ 2026-08-29 Architecture Decisions — Telling Apart What You Can Undo From What You Cannot How to separate the design decisions you can cheaply reverse f Engineering Process · ★ 🤖 2026-10-10 · Paper walkthroughs SafeActBench explained (arXiv:2610.07753) — tool agents fail before execution A correct outcome does not mean the action was supported by ev Agents 🏭 2026-08-29 EDA Tools from Scratch — Chips Are Written in Software Nobody hand-places the tens of billions of transistors on a le Supply Chain · ★ ◆ 2026-08-26 Approximation Algorithms — Trading Exactness for a Guarantee The craft of giving up on the optimal answer while attaching a Complexity · ★ 🎲 2026-08-27 Monte Carlo Methods from Scratch — Solving Integrals with Dice An integral you cannot solve can still be estimated: scatter r Probability & Statistics · ★ ◆ 2026-08-25 WebP, AVIF, JPEG XL — The Image Codec Changing of the Guard Three successors clearly beat JPEG on efficiency, and the web Image Codecs · ★ ◆ 2026-08-29 Upstream Work in the AI Era — When Code Gets Cheap, What Gets Valuable? When implementation gets cheap, which parts of the cost remain Engineering Process · ★ 📄 2026-10-10 · Paper walkthroughs Paper Explained: EVISKILL — Rewriting an Agent's Playbook from Replayable Evidence A framework for automatically revising an LLM agent's skill do Paper Deep-Dives · ★ 🏭 2026-08-29 The Geopolitics of Chips — Export Controls and Supply Chain Rewiring, Explained Technically Why chokepoints form exactly where they do, from three conditi Supply Chain · ★ ◆ 2026-08-25 NP-Completeness from Scratch — Not Unsolvable, but Fast to Verify NP does not stand for Non-Polynomial. It is the class of probl Complexity 🎲 2026-08-27 · Paper walkthroughs Kernel Methods and Gaussian Processes — The Champions Before Neural Nets Before deep learning took over, kernel SVMs held the crown in Probability & Statistics · ★ ◆ 2026-08-22 Motion Compensation from Scratch — Where 90% of Video Compression Happens What decides where a video codec's bits go isn't the transform Video Codecs · ★ ◆ 2026-08-27 File Systems from Scratch — What Does "Saved" Actually Guarantee? If the power dies half a second after your editor says "Saved, OS & Runtime · ★ ◆ 2026-10-09 · Paper walkthroughs Paper Explained: STEPQuant — When and Where Quantization Errors Matter in Delta-Rule Recurrent States Linear-attention states have a fixed size, yet under concurren Time Series · ★ 🔬 2026-08-27 The Physics of NAND Flash — Remembering by Trapping Electrons Why does a memory stick keep your photos with the power off? S Device Physics · ★ ◆ 2026-08-25 Simulated Annealing and Genetic Algorithms — What to Do When Exact Solving Breaks Down Why search methods that guarantee nothing end up running real Search & Optimization · ★ ◆ 2026-08-27 Jacobians and Hessians — Multivariable Calculus, Drawn The Jacobian is a magnifying glass at a point; the Hessian is Calculus & Optimization · ★ ◆ 2026-08-22 MP3 and Psychoacoustics — The Science of Sounds You Cannot Hear MP3 does not throw away sounds that aren't there — it throws a Audio Codecs ◆ 2026-08-27 · Paper walkthroughs Distributed Databases — CAP, Replication and Consensus The moment you add a second copy of your database, a brand-new Databases · ★

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Written from the papers themselves. Every piece links the paper page and its PDF.

◉AI248

  1. Paper Explained: Holi-World — Turning First-Person Recordings into a Ledger of the Room, Then Teaching a VLM to Reason over It ★ MEMBER arXiv:2610.26549
  2. Paper Explained: Refusal in Language Models Is Mediated by a Single Direction — saying "no" lives on one line inside the model ★ MEMBER arXiv:2406.11717
  3. Paper Walkthrough: Dynamic Band Splitting — Letting Each Mixture Decide Where the Frequency Bands Go ★ MEMBER arXiv:2610.14993
  4. Paper Deep Dive: Transformers Stop Thinking Too Early — How a One-Layer Rank-8 LoRA Stretches 3-Line Reference Following to 50 ★ MEMBER "arXiv:2609.36585
  5. Paper Deep Dive: From Evidence to Action: How Tool-Using Agents Fail — Reading the Failure Diagnostics and Interventions ★ MEMBER arXiv:2610.07753

See all 248articles →

▣Semiconductors4

  1. CPU Pipelines and Branch Prediction — The Factory Inside One Clock Tick ★ MEMBER arXiv:1801.01203
  2. Systolic Arrays — Building the Heart of the TPU From Scratch ★ MEMBER arXiv:1704.04760
  3. The GPU Memory Hierarchy — HBM, SRAM, Registers, and Why Movement Wins FREE arXiv:2205.14135
  4. How AI Accelerators Are Designed — What Actually Separates GPUs, NPUs, and TPUs ★ MEMBER arXiv:1704.04760

◇Algorithms5

  1. The Fourier Transform from Scratch — Reading a Signal as a Stack of Pure Tones FREE Fourier 1822
  2. Probabilistic Data Structures — Counting Without Counting ★ MEMBER "doi:10.1145/362686.362692
  3. The FFT from Scratch — Why Convolution Turns into Multiplication ★ MEMBER "doi:10.1090/S0025-5718-1965-0178586-1
  4. Graph Algorithms from Scratch — Shortest Paths and Where They Lead FREE arXiv:1603.09320
  5. Hashing and Nearest-Neighbor Search — The Groundwork Under Vector Search FREE arXiv:1603.09320

∫Math for AI14

  1. Bayes' Theorem from Scratch — Why a 99% Accurate Test Can Be a Coin Flip FREE Bayes 1763
  2. Gradient Descent from Scratch — The Geometry of Learning FREE arXiv:1609.04747
  3. PCA from Scratch — Eigenvectors as the Axes of Your Data FREE Pearson 1901
  4. Compression Is Prediction Is Intelligence — LLMs Through Information Theory ★ MEMBER arXiv:2309.10668
  5. Symmetry and Equivariance — How Group Theory Shapes Network Design ★ MEMBER arXiv:1602.07576

See all 14articles →

◐Media & Compression3

  1. Neural Audio Codecs — EnCodec and the Foundation Under Speech LLMs ★ MEMBER arXiv:2210.13438
  2. Neural Compression — The Codec That Learns ★ MEMBER arXiv:1611.01704
  3. Why Opus Won — The Design of a Modern Audio Codec ★ MEMBER RFC 6716

⬢Systems3

  1. RSA from Scratch — The Number Theory Behind Public Keys FREE "Rivest
  2. Distributed Databases — CAP, Replication and Consensus ★ MEMBER "USENIX ATC 2014
  3. LLM Security — Prompt Injection and How to Actually Defend Against It ★ MEMBER arXiv:2302.12173
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