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A five-minute animated explainer of liquid democracy, in which voters can delegate their vote to trusted people. It starts from the origins of democracy and contrasts direct and representative models.

PolyMatter's first part of a series on China's demographic collapse, covering the effects of the one-child policy, shrinking workforce and economic consequences.

Veritasium explains why no voting system can be perfectly fair, drawing on Arrow's theorem and the work of Eric Maskin. It looks at problems with systems like first-past-the-post and ranked-choice voting.

Kurzgesagt explains how the European Union is governed, how its officials are elected or appointed, and whether a citizen's vote actually matters.

CGP Grey explains the City of London's unusual governance, including the Lord Mayor, guilds, and how it differs from the rest of London.

A Kurzgesagt animation on South Korea's record-low fertility rate and rapidly aging population. It explains why a demographic collapse looks hard to reverse and projects the population shrinking sharply by 2060.

Veritasium visits the National High Magnetic Field Laboratory to see the world's strongest magnets and demonstrate effects like eddy currents. It covers what intense magnetic fields do to materials and objects.

Veritasium revisits Thomas Young's original double slit experiment with light, showing how interference supports the wave nature of light. It uses a pond-wave demonstration to explain the pattern.

Steve Mould shows that LEDs and solar panels are both diodes made from semiconductors, so a solar panel can emit light and an LED can generate electricity. He demonstrates a small solar panel lighting up.

A Kurzgesagt explainer on why the human population exploded and why growth is slowing, drawing on Our World in Data. It argues that birth rates fall as countries develop, easing overpopulation fears.

Huygens Optics explains the Fourier transform and shows how a lens performs one optically. A DLP projector is used as a Fourier filter to do simple pattern recognition on lithographic character patterns.

Veritasium explains why bicycles are stable, arguing that gyroscopic effects are not the answer. The video shows countersteering and an experiment where riders blocked from steering the opposite way cannot turn.

Veritasium asks people where a tree's mass comes from, then explains that most of a dry tree's mass originates from carbon dioxide in the air. It combines street interviews with a short explanation of photosynthesis.

Numberphile with Tom Crawford of Oxford explains the Reynolds number, the second of three videos on Navier-Stokes and fluid flow, with demonstrations of laminar versus turbulent behavior.

Tech Ingredients explains the principles of magnetohydrodynamics and builds several demonstrations, including propelling liquid metal and electrolytes with magnets and a railgun-style setup.

Tech Ingredients demonstrates how microwaves work and how they affect objects at range, then shows ways to defend against them. It includes a correction about rectifier output frequency.

Retro Game Mechanics Explained shows how the Atari 2600 draws images with almost no video memory, by having the CPU race the CRT beam line by line. It walks through the techniques in detail.

Tom Scott tours the rotating room artificial gravity facility at Brandeis University's Graybiel lab. It shows how humans cope with rotation-based gravity and the odd effects such as Coriolis forces.

Nature video showing MIT researchers flying the first plane with no moving parts, powered by an ion drive that creates an ionic wind from high-powered electrodes. The 5m-wide craft flies across a sports hall.

Veritasium explores how synchronization arises spontaneously in nature, with metronomes, fireflies and bridges, drawing on Steven Strogatz's work on chaos and complexity.

Technology Connections explains how RGB light and color work, from hue and saturation to color vision and how objects appear under different lighting. It uses a studio setup with colored lights to demonstrate the effects.

CGP Grey explains first-past-the-post voting and why it pushes elections toward two dominant parties. It is the first in his series on electoral systems.

Veritasium recounts a $10,000 bet with a UCLA physics professor over whether a vehicle can travel downwind faster than the wind. He presents the professor's reasoning and demonstrations, including one without aerodynamics.

Technology Connections explains how heat pumps work as reversed air conditioners and why they can deliver several times the heat of resistive heating per unit of energy. It also tackles common myths such as poor cold-weather performance.

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

Technology Connections explains how old-fashioned non-electronic rice cookers work, using a magnet and spring switch tripped by the Curie point. It shows the thermodynamics and magnetism behind a simple appliance.

The 8-Bit Guy covers IBM's 1981 CGA graphics system, including how composite output and artifacting produced extra colors beyond the nominal palette. He argues CGA looked better in period than it does on RGB monitors.

A short video from the trafficwaves.org site showing how traffic jams and standing waves form, including the fight between cheaters and blockers at an exit-lane backup. It also touches on how individual driving behavior affects the flow.

Veritasium explains how trees lift water from roots to the top of tall trunks, using transpiration pull and the negative pressure that liquid water can sustain. It explains why trees do not need pumps or valves.

A Smarter Every Day episode from aboard a nuclear submarine on how the crew makes breathable air. It covers oxygen generation from seawater, oxygen candles and CO2 scrubbing with amine.

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.

Veritasium's Derek Muller visits NASA JPL to see the Mars helicopter Ingenuity before it was mounted on the rover. He explains how it can fly in Mars's thin atmosphere with large, fast-spinning contra-rotating rotors and low mass, and covers power and cold.

Benn Jordan investigates infrasound and low-frequency noise from data centers, including xAI's Colossus and a crypto mine, and reports his own experiments on the effects. The video covers the health and community impacts on nearby residents.

A minutephysics explainer showing that the Moon's path around the Sun is not a spiral but closer to a 12-sided polygon with curved corners. It argues the Moon arguably orbits the Sun rather than the Earth.

Veritasium shows silicone oil droplets bouncing on a vibrating bath, a physical analogue of pilot wave theory that reproduces quantum-like behavior such as double-slit patterns.

Veritasium explores compliant mechanisms, devices that move by flexing rather than using hinges and joints, with researchers at BYU. It covers advantages such as fewer parts and precision, including uses in nuclear weapon safety.

Smarter Every Day shares a binaural audio recording of the SpaceX Falcon Heavy launch made by Trevor Mahlmann, with explanations of the sounds including the sonic booms of the landing boosters. It is meant to be heard with headphones.

Tom Scott stands by a construction site and explains why reversing vehicles now use a white-noise hiss instead of beeping. The sound is easier to locate directionally and less annoying to neighbours.

Richard Feynman, in a clip from the BBC series Fun to Imagine, takes on the puzzle of why mirrors seem to swap left and right but not top and bottom.

A minutephysics video explaining why a piano cannot be perfectly tuned, comparing equal temperament with just intonation and the math of harmonics.