background checks

Tom Scott explains Electrical Network Frequency analysis, where hum from the power grid in a recording is matched against grid logs to date and place it. He talks to a researcher and sets them a challenge.

An 11-minute animated introduction to P vs. NP and the wider landscape of complexity classes, inspired by the Complexity Zoo wiki. It assumes no background in computer science.

Episode 4 of Mike Maloney's Hidden Secrets of Money, explaining how currency is created through a chain of IOUs among the Treasury, banks and the Federal Reserve. It covers bonds, Fed checks, debt, taxes and fractional reserve lending, from a gold-and-silver advocate's viewpoint.

Techmoan's beginner introduction to the compact cassette, testing metal tapes and Dolby S noise reduction on a Sony TC-S1 deck. He checks whether a cassette can sound close to a CD when good tape and equipment are used.

Yannic Kilcher walks through the Attention Is All You Need paper, which introduced the Transformer, a sequence model based solely on attention without recurrence or convolutions. He reviews the architecture and the paper's translation results.

A Wendover Productions explainer on the political agreements, from the Chicago Convention onward, that determine which airlines can fly where. It lays out the five freedoms of the air.

RealLifeLore explains France's military posture towards Russia, including French involvement in Africa and Russian influence in the Sahel. It covers the geopolitics behind current tensions.

Astrophysicist Dr. Becky explains the Hubble tension, the disagreement between expansion-rate measurements from the cosmic microwave background and the distance ladder, and what early JWST Cepheid observations add.

FortNine argues that the US DOT motorcycle helmet standard (FMVSS 218) is badly outdated and weak. It compares it with Snell and ECE standards and points to where you can look up test reports for your own helmet.

Tom Scott visits the US National Helium Reserve in Amarillo, Texas, and explains why headlines that the world is running out of helium are misleading. He covers the Federal Helium Program and its planned privatization.