measurement

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.

Ben Krasnow of Applied Science shows that a plain laser diode can measure sub-micron vibrations from centimeters away using self-mixing interferometry, and can also be used for range-finding.

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.

Ron Garret's Google Tech Talk argues that quantum mechanics is no harder to understand than relativity and that popular accounts wrongly rely on the Copenhagen interpretation. He presents measurement as entanglement and explains phenomena like the quantum eraser.

Gil Tene of Azul Systems explains common pitfalls in measuring latency and response time, including why averages mislead and the problem of coordinated omission. He introduces open source tools like HdrHistogram for better measurement and reporting.

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.

Emery Berger argues that performance is hard to measure and deliver on modern systems, showing how code layout and link order can swamp optimization effects. He presents tools that evaluate performance more reliably.

Matt Parker of Stand-up Maths asks whether a country's reported land area accounts for hills and mountains, working through how surface area depends on the resolution of elevation data. It follows up on a question from a viewer and work by researchers who measured it.

PBS Space Time explains the Bohr-Einstein debate over quantum mechanics and how quantum entanglement settled it. It covers the weirdness of measurement and nonlocal correlations.

Terence Tao's AMS Einstein Public Lecture at UCLA on the cosmic distance ladder, the chain of methods astronomers use to measure distances from the Earth to distant galaxies. It is aimed at a general audience.

Physicist Jacob Barandes discusses his view that quantum mechanics can be formulated without wave functions, using a stochastic, probabilistic approach. The long interview covers measurement, the foundations of quantum theory and the history of the field.

Emery Berger explains why performance is hard to measure and deliver on modern hardware, showing how code layout and alignment can swamp optimization effects. He presents Stabilizer for statistically sound evaluation and Coz, a causal profiler.

3Blue1Brown shows how the uncertainty principle arises from Fourier transforms. A wave packet cannot be narrow in both position and frequency, so the principle is a property of waves rather than of measurement.

Floyd Toole's CIRMMT distinguished lecture on the science of sound reproduction, drawing on decades of blind listening research. It covers what listeners prefer in loudspeakers and why measured accuracy and anechoic response matter.

Terence Tao and Grant Sanderson of 3Blue1Brown walk through the cosmic distance ladder, showing how humans measured distances from the Earth to the Moon, Sun, planets and beyond. It includes animations and the history behind each step.

A short video of Robert F. Kennedy's 1968 speech criticizing Gross Domestic Product as a measure of progress, saying it counts everything except what makes life worthwhile.

Emery Berger's CppCon 2020 plenary on why performance is hard on modern hardware after the end of Dennard scaling. It covers benchmarking pitfalls and introduces new profiling tools for finding real bottlenecks.

Big Clive tears down a cheap eBay digital caliper, explaining its capacitive linear encoder and measuring its quiescent current. He finds it surprisingly accurate and repeatable for its price.

Ben Krasnow of Applied Science builds a DIY microbalance from an analog panel meter with an optical servo loop. It reaches about 5 micrograms of precision and is used to weigh a single eyelash at around 35 micrograms.

Veritasium explains that the US signed the Metre Convention in 1875 and that all US customary units are officially defined in terms of metric standards. It also touches on the standard kilogram.

A Real World Crypto 2017 talk by a Google engineer on using private set intersection to match ad views with in-store purchases. It describes privacy-preserving matching that avoids exposing personal transactions.

A two-minute Telegraph report that takes a decibel meter to a wind farm and nearby residential areas to measure how loud turbines are compared with everyday noise.

AlphaPhoenix builds a scaled-down version of the Veritasium electricity thought experiment using about a kilometer of wire and an oscilloscope. He measures how the signal actually propagates and explains the result.

Matthias Wandel uses anemometer measurements to find where to place a fan to move the most air through a house at night. He finds that placing the fan some distance back from the window works better.

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 PBS Space Time episode on how the Higgs mechanism gives particles mass, prompted by Fermilab's heavier-than-expected W boson measurement. It goes beyond the usual pop-science treatment without heavy math.

Steve Hsu's 2011 Google Tech Talk reviews psychometric measurement of intelligence and the heritability of adult IQ, then discusses genome-wide association studies seeking the genes behind cognitive ability.

Marco Reps builds and tests an open-source 8.5 digit voltmeter based on CERN's high-precision ADC design. The video walks through assembly, soldering and measurement of the resulting instrument.

ElectroBOOM examines whether 5G and other electromagnetic waves can harm people, explaining the EM spectrum and the difference between ionizing and non-ionizing radiation. It includes experiments and measurements in his usual humorous style.

HDTVTest reviews the Apple Pro Display XDR using measurements and a side-by-side comparison with a Sony BVM-HX310 dual-layer LCD reference monitor. It examines how well the display handles HDR against a professional reference.

Der8auer visits Tescan and uses an electron microscope to compare real transistor sizes on Intel 14nm and AMD 7nm chips. It shows that process node names do not match physical measurements.

A look at how granite surface plates are inspected, calibrated and reconditioned using an autocollimator, a repeat meter and diamond-charged cast iron laps. Measurements are at the level of millionths of an inch.

Inventor Mary Lou Jepsen demonstrates using red light and sound to see inside the body and brain, aiming at tumor detection and neural activity measurement, and potentially a cheaper wearable MRI replacement.

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.

Technology Connections tests how quickly gas, induction and standard electric stoves boil water, with CO2 measurements and a discussion of the advantages and disadvantages of each.