lock-free

CuriousMarc powers up a vintage HP 5061A cesium beam clock and explains both the quantum principle and the HP implementation in detail. It is part of a longer atomic clock series.

Practical Engineering explains how canal locks work, including the water-saving basins of the new Panama Canal locks.

Not Just Bikes visits the Toronto Islands, home to Canada's only car-free neighbourhood. He explains the waiting list and strict ownership rules and asks why more such places aren't built.

A short Vox video on Barcelona's superblocks, an urban design approach that closes interior streets to through traffic to return space to pedestrians.

Technology Connections explains how refrigerator and freezer design affects energy use, using chest freezers to show why top-opening designs and layout choices matter. It includes thermal-camera footage of cold air spilling out of upright units.

3Blue1Brown explains the math and mechanics behind Bitcoin visually: ledgers, digital signatures, proof of work and the blockchain, building up a decentralized payment system from first principles.

A Technology Connections video essay on how analog and digital clocks shape different mental models of time, with the minute hand acting as a progress indicator.

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.

Not Just Bikes explains the Dutch concept of autoluw, or nearly car-free, streets and how it is applied across the Netherlands, with examples from Toronto and Copenhagen. It also covers Amsterdam's move toward a nearly car-free city.

Sabine Hossenfelder explains superdeterminism as an interpretation of quantum mechanics, addressing common objections and misconceptions, including the worry that it kills free will or science. She ties it to Bell's theorem and hidden variables.

Sciencium examines the Mpemba effect, the claim that hot water freezes faster than cold water. It walks through experiments and a published paper questioning the effect.

Tom Scott investigates the claim that the microwave was invented to heat hamsters, and interviews James Lovelock about freezing and microwave-thawing hamsters in the 1950s. It traces early magnetron uses beyond radar.

A three-minute excerpt from Milton Friedman's Free to Choose in which he uses a pencil to show that no single person knows how to make it. He argues that the free market coordinates countless strangers peacefully.

Numberphile visits YouTube to learn why view counts on new videos used to freeze at 301. It explains that YouTube holds counts while it verifies views aren't from bots or fakes.

A Vox explainer on how mandatory parking minimums and free parking impose hidden costs on cities. It draws on Donald Shoup's work and gives the history of parking requirements.

A two-minute clip in which Milton Friedman uses a humble pencil to show how thousands of strangers across many countries cooperate, without central direction, to make a simple product. It is a short visual version of the 'I, Pencil' essay's argument about free markets and dispersed knowledge.

Veritasium explains why the one-way speed of light has never been measured, only the round-trip speed, since measuring it requires synchronized clocks that assume the answer. It explores the implications for relativity.

An illustrated 23-minute summary of David Friedman's talk based on The Machinery of Freedom. It describes how law, police and courts could work as market services in a stateless society, covering private law, polycentric law and objections.

An animated visualization of basic quantum mechanics using a free particle, with simulations based on the actual equations. It covers waves, particles, and how measurement collapses the wavefunction.

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.

Benn Jordan explains how Flock Safety's license plate cameras log and share vehicle locations, and explores how adversarial AI can defeat them. It covers weak security and the surveillance risks of private police-camera networks.

A five-minute CGP Grey explainer arguing that a phone is effectively an extension of your mind, and that any backdoor or master key into encrypted devices will inevitably be abused or leaked. It frames the encryption debate as locks that are either unbreakable or absent.

An MTA video on communications-based train control, the system meant to replace the New York City subway's century-old signaling. It also shows the mechanical interlocks and signals in use today.

Sabine Hossenfelder explains how special relativity leads to the block universe, in which past, present and future all exist equally, and asks what that means for whether the past still exists.

Tom Scott explains the famous Dutch flower auction clock at Royal FloraHolland in Aalsmeer, a literal Dutch auction, and how the internet changed it. It is a short look at how the system worked then and now.

Tom Scott explains why electronic voting is a bad idea. Elections must be trusted by everyone and attacks on software scale in ways attacks on paper do not, so open source or blockchain fixes do not solve it.

CGP Grey argues that your brain treats a whole home as one room during lockdown, blurring work, rest and leisure. He recommends creating separate spaces and routines for different activities to stay balanced.

Veritasium explains, with expert input, that in general relativity gravity is not a force and objects follow straight paths through curved spacetime, including why standing on the ground means you are accelerating.

Historia Civilis traces the history of work and time discipline, comparing modern working hours with those of medieval peasants and the changes brought by clocks and industrialization. It draws on works such as Schor's The Overworked American.

Adam Savage shows a set of Mitutoyo ceramic gauge blocks and uses them to explain metrology, the science of measurement. He argues that accuracy and precision work differently than most people assume, which changes how you think about every measuring tool.

CityNerd Ray Delahanty explains induced demand and what happens when freeways are widened. He walks through the economics of supply and demand applied to traffic and asks how much new traffic appears and whether congestion returns.

Technology Connections takes apart a 1970 Wurlitzer 3400 jukebox to show how electromechanical relays and switches automated its behavior without a computer.

Marques Brownlee explains why iMessage's blue and green bubbles matter, covering the technical, commercial and social side of Apple's messaging lock-in. It also discusses RCS and what could be done about it.

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.

Not Just Bikes explains Dutch bicycle-only roads, which let people travel long distances in and out of cities with almost no car interaction. It shows how this changes cycling from a chore into something enjoyable.

Tom Scott visits ThyssenKrupp's test tower in Rottweil to see the Multi, a rope-free elevator that uses linear motors to move cabins sideways as well as vertically.

A scene from The Big Short in which Jared Vennett pitches credit default swaps on mortgage bonds to a hedge fund team, using a Jenga tower to illustrate collateralized debt obligations.

Zack Freedman gives advice on why makers fail to finish projects, including scrapping bad ideas, showing work publicly and writing a plan that keeps projects fun. It is aimed at hardware DIY but generalizes.

WIRED has UCLA professor Amit Sahai explain zero-knowledge proofs to a child, a teen, a college student, a grad student and an expert. Each round goes deeper into the cryptography and why it matters.

A short film from the Competitive Enterprise Institute adapting Leonard Read's 1958 essay I, Pencil, showing how no one person knows how to make a pencil and how many people cooperate without central planning.