information processing

3Blue1Brown uses Wordle as an excuse to teach information theory and entropy, building a solver that picks guesses by expected information and incorporating word frequencies.

Reducible's visual walkthrough of the Fast Fourier Transform, motivated by polynomial multiplication. It shows how the FFT's key ideas can be discovered by asking the right questions.

3Blue1Brown's discovery-oriented introduction to error correction codes, building up Hamming codes from the puzzle of locating a flipped bit. It explains the parity-check idea and why it is so efficient.

Veritasium tells the story of the Fast Fourier Transform, from its use in detecting nuclear tests to Cold War politics, and how it could have changed the arms race. It includes a short, intuitive explanation of what the Fourier transform does.

Monty Montgomery of Xiph.org gives real-time demonstrations of sampling, quantization, bit depth and dither using real audio equipment, including both digital analysis tools and vintage analog bench gear. It shows that sampled audio is not stair-stepped and corrects common misconceptions about digital audio.

3Blue1Brown introduces Fourier series, from the heat equation to drawing arbitrary shapes with rotating circles. It builds a visual intuition for decomposing functions into sine waves.

GoldenSound publishes music on Tidal to test MQA, a deep dive into the format's claims and problems including its leaky filter. Testing begins around the 5:45 mark.

Mathologer explains epicycles and complex Fourier series, inspired by an animation of Homer Simpson drawn with epicycles. It covers the shape of the Moon's orbit around the Sun and how to make your own epicycle drawings.

Veritasium builds a QR code by hand to explain how it works. It covers the history of Morse code and barcodes, how QR codes encode data, why damaged codes still scan, and how safe they are.

Science journalist potholer54 examines the claim that SARS-CoV-2 came from a Wuhan lab, tracing the sources behind it and the weaknesses in the evidence.

Destin Sandlin of Smarter Every Day investigates manipulation on Facebook, interviewing the company's team about content moderation. It is the third video in his series on social media manipulation.

Destin Sandlin of Smarter Every Day examines how bad actors and bots use Twitter, drawing on the released Russian IRA dataset and interviews. It asks why interactions on the platform turn hostile.

A Technology Connections video on how ground-source (geothermal) heat pumps work and why they hold efficiency in winter. It also covers related heat pump information, and the description notes air-source heat pumps have since improved.

Technology Connections takes apart the step-by-step electromechanical logic of a 1970s pinball machine. He shows how relays, steppers and switches track state and score without electronics.

Veritasium presents David Sinclair's information theory of aging, which says aging is a loss of epigenetic information, and the evidence that aging can be slowed or reversed. It touches on stressors like fasting, exercise and cold exposure.