partial state

Veritasium explains how investigators caught the Golden State Killer using forensic genealogy, matching crime scene DNA to distant relatives in public genealogy databases. It also covers the privacy implications of DNA databases.

2swap explains how he solved the Klotski sliding-block puzzle by mapping its full state space as a graph and visualizing it. The video includes footage of the Guinness world-record solve and links to an interactive graph.

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.

Not Just Bikes argues that people in walkable, bikeable Dutch cities stay healthy because exercise is built into daily life, which he calls the gym of life. It contrasts this with car-dependent cities that require deliberate workouts.

Kraut traces centuries of political development, from Mongol rule and the Orthodox church to Muscovite autocracy, that shaped Russia's authoritarian state. It uses countryball animation and compares Russia with Europe and China.

A Vox explainer from the 2020 election series on why American public transit is so poor. It traces the effect of the interstate highway system on cities and the resulting car dependence.

An Asianometry explainer on why the Soviet Union, once a leading computing power, fell far behind the US in computers by the 1980s. It traces the gap from the 1960s onward despite strong state support for science.

A short explainer from 2swap on the chaotic behavior of double pendulums. It examines how predictable the system is for some starting conditions and whether closed-form solutions exist.