dependent types

Professor Brailsford of the University of Nottingham describes how the university set out to print its own mathematics exam papers in the 1980s. The story centers on getting a Mergenthaler Linotron 202 typesetter to work with their own software.

Matt Parker talks Numberphile through the different kinds of numbers: algebraic, transcendental, computable, normal, and beyond. It shows how few numbers we can actually name or describe.

Not Just Bikes explains that car-dependent suburbs are not the only option, using Toronto's Riverdale as an example of a pre-war streetcar suburb. These walkable neighborhoods are popular but are now effectively illegal to build.

Not Just Bikes explains the Strong Towns argument that car-dependent American suburbs cost more to maintain than they generate in taxes. It describes the growth Ponzi scheme that props up municipal finances.

Technology Connections explains why brown is not a spectral color but a context-dependent perception, essentially dark orange seen against brighter surroundings.

Practical Engineering's explanation of the February 2021 Texas winter storm and the resulting power grid outage. It lays out the facts about ERCOT, the grid's isolation, and how generation across fuel types failed in the cold.

CGP Grey explains split-brain patients, where severing the corpus callosum lets the two hemispheres act independently. He uses this to explore the idea of two minds in one head.

Not Just Bikes argues that car-dependent suburbs rob children of independence, contrasting North American suburbia with Dutch cities where kids walk and bike on their own. It is the creator's remake of an earlier video on the topic.

Not Just Bikes explains, using Urban3's property-tax analysis, why car-dependent suburbs generate less tax revenue than they cost to maintain, so dense urban cores effectively subsidize them. It is part of a Strong Towns series.

Everyday Astronaut explains the basic physics of rocket engines, the main engine cycles and fuel types, then compares SpaceX's methane-fueled full-flow staged combustion Raptor to other engines. It runs nearly 50 minutes with chapter markers.

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.

Technology Connections explains why humidity matters and compares the main types of humidifiers, including evaporative and ultrasonic designs. It covers how and why you would add moisture to indoor air.

PBS Space Time explains the Hubble constant tension, in which two precise, independent methods of measuring the universe's expansion rate disagree. It covers why this calls some standard cosmology into question.

Matthias Wandel tests old and new code on a range of PCs, including a new mini PC, to measure how much faster modern hardware really is. He also shows optimization techniques such as branchless code, with benchmark programs on GitHub.

Not Just Bikes contrasts typical car-dependent North American business parks with one near the airport in the Netherlands that works for driving, cycling and transit. It looks at how the design makes commuting easier.

Veritasium visits the US Navy's Crane facility to test top night vision goggles. It explains how image intensifier tubes and thermal or digital systems work and compares the generations of the technology.

Wendover Productions explains why American towns, retail and buildings increasingly look alike, covering zoning pressures, corporate standardization and cheap construction types like 5-over-1 buildings.

A short PBS Eons episode on carcinization, the repeated independent evolution of crab-like bodies in unrelated crustaceans, and what makes that form so successful.

Not Just Bikes tours Houten, a Dutch town designed around cycling, explaining how its layout makes most trips by bike safe and easy. It also promotes a book about the town.

Quanta Magazine explains the 2022 experiment that claimed to create a holographic wormhole on Google's quantum computer. The description now notes that a later independent analysis questioned whether any wormhole was created.

Not Just Bikes examines Toronto's GO Transit commuter rail, arguing it is a costly system with park-and-ride stations and rush-hour-only service that subsidizes car-dependent suburbs.