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PBS Space Time explains Roger Penrose's conformal cyclic cosmology, in which the far future of our universe becomes the big bang of the next. It explores what could come after the universe ends.

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.

Astronomer David Kipping of Cool Worlds talks with Mick West to break down the three declassified Pentagon UFO videos. They explain the footage through camera artifacts, glare, and perspective effects.

Lindybeige gives an hour-long history of English coinage and the problems of maintaining a trustworthy currency. It ends with an explanation of why the pounds, shillings and pence system worked so well.

PBS Space Time examines Roger Penrose's idea that consciousness arises from quantum processes in the brain, and reviews new evidence about microtubules. It ends with an estimate of what replicating consciousness would demand.

Tom Scott's video whose title shows its own live view count, and the story of how he made that work. It explains why open APIs were once common and why they largely disappeared.

Technology Connections spends 22 minutes on the humble can opener and what its design shows about products and why people don't know what to look for. It uses an everyday tool to draw broader lessons.

CityNerd's Ray Delahanty tallies the personal costs of driving and then the externalities that car dependency imposes on everyone else, with numbers for each. It is an urbanist case that driving is heavily subsidized and costs society far more than drivers pay.

Veritasium visits NIST to explain Standard Reference Materials, the carefully characterized items such as peanut butter used to calibrate instruments and keep measurements consistent. It covers why they exist and why they are expensive.

A CGP Grey video about why pentagons are bad at tiling and why hexagons are so special, in his usual playful style. It touches on honeycombs and tiling in nature.

Veritasium explores what general relativity says about black holes, white holes and wormholes, with help from physicists Geraint Lewis and Juan Maldacena. It introduces Penrose diagrams and the idea that other universes may be implied.

Not Just Bikes introduces the "stroad", a street-road hybrid common in the US and Canada that fails at both jobs. He contrasts it with Dutch design, where each road has a single purpose, and covers cost, danger and ugliness.

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.

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.

The first video in Not Just Bikes' Strong Towns series explains the financial instability of North American cities, based on Strong Towns research. It argues that low-density suburban growth costs more to maintain than it brings in.

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.

Tantacrul explains how he and engraver Simon Smith designed the free music notation font for MuseScore 3.6. It draws on the history of the SCORE notation application by Leland Smith.

Not Just Bikes explains how small pockets of shops and restaurants inside residential Dutch neighbourhoods create liveliness and help reduce traffic. It argues this kind of mixed-use design has been illegal in most of the US and Canada for a century because of zoning, and should be brought back.

Veritasium explains how Penrose tilings and quasicrystals overturned the belief that 5-fold symmetry and non-periodic crystals were impossible, including an interview with Paul Steinhardt.

A Climate Town video on how the auto industry reshaped American cities and culture through advertising, lobbying and campaigns like the 1939 World's Fair. It is snarky in tone but backed by a published source document.

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.

Modern Vintage Gamer looks at OpenLara, an open source Tomb Raider engine, running on the Game Boy Advance. The video explains how the port achieves playable speeds on the GBA's slow ARM CPU, with input from the developer XProger.

Practical Engineering explains why San Francisco's Millennium Tower is sinking and tilting, covering how geology and foundation design (friction piles in the Colma Formation) affect skyscrapers. It also covers the fix being attempted.

JerryRigEverything tours Li-Cycle to show how lithium-ion batteries from EVs, phones and tools are recycled. It walks through the process of shredding batteries and extracting materials.

Randall Munroe of xkcd answers what would happen if you swam in a spent nuclear fuel pool, and how much radiation you would receive at the surface versus at depth.

Practical Engineering summarizes the 2017 Oroville Dam spillway failure, explaining the engineering details behind the incident. It also discusses how operators and regulators failed to keep downstream residents safe.

Not Just Bikes reflects on five years in the Netherlands and tours small towns and cities, from Haarlem to Veenendaal. It argues that good urbanism with walkable streets, bike infrastructure and transit is found almost everywhere there, not just in Amsterdam.

Ben Felix examines whether the well-known 4% retirement withdrawal rule holds up, drawing on academic papers. He argues that a safe rate may be closer to 2.7%, especially for early retirees.

Oh The Urbanity! tests the theory that banning housing investors would fix affordability, using Rotterdam's ban as a case study. The video finds mixed results.

Climate Town traces the history of American parking minimums, how they came from shaky research and ITE guides, and how they shape zoning, cities and housing costs. It is a long, comedic video essay.

Not Just Bikes takes on the common excuse that a country is simply too big or spread out for good transit and walkable cities. The video argues that city density and short everyday trips matter, not national size or overall population density.

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.

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.

Not Just Bikes looks at traffic in the Bahamas to show that a small country can be just as car-centric as a big one. He ties it to land use, car dependence and how dedicated transit lanes help.

Not Just Bikes explains how North American speed limits are set and why posted limits matter far less than street design. It argues that drivers follow the road's cues, so safe speeds have to be built into the street.

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

Veritasium argues that electric energy is carried by fields around the wires rather than by electrons moving through them, using a thought experiment with a large circuit.

AlphaPhoenix uses a custom high-speed measurement setup to watch voltage waves travel down wires and split at a fork. It answers how electricity knows where to go and how quickly that process happens.

3Blue1Brown visualizes Feynman's lecture on the refractive index, explaining why light appears to slow down in glass and why the effect depends on color. It builds the idea from waves produced by oscillating charges in the material.

Practical Engineering explains what a black start is: restarting a power grid after total collapse. It shows why most plants need outside power to start and why rebuilding a synchronized grid is delicate and high-stakes.