The History of Physics Podcast

From a simple gnomon in 240 BCE to an estimate of Earth's circumference within a few percent, this episode follows ancient Greek astronomer Eratosthenes and how he used shadows to quantify our planet. It shows how early measurement, critical questioning, and knowledge sharing paved the way for modern scientific methodology.

Learn more about your ad choices. Visit megaphone.fm/adchoices

In this episode we trace how a 2,600‑year‑old observation of light through a tiny hole—recorded by the philosopher Mozi—laid the first geometric foundation for optics. We explore how this simple experiment challenged prevailing ideas about light in ancient China, influenced Tang‑dynasty art and perspective, and prefigured later developments from Euclid to Maxwell.

Learn more about your ad choices. Visit megaphone.fm/adchoices

In spring 1820, Hans Christian Ørsted discovered that an electric current deflects a compass needle, revealing the intimate link between electricity and magnetism. This simple experiment set off a chain of discoveries—from Faraday’s induction to Maxwell’s equations—that underpin modern electrical technology.

Learn more about your ad choices. Visit megaphone.fm/adchoices

Tycho Brahe’s 1572 supernova startled a world that still believed in immutable heavens. By measuring its position with unprecedented precision and finding no parallax, he proved the new star lay beyond the Moon—upending Aristotelian cosmology and laying groundwork for Kepler and modern astronomy.

Learn more about your ad choices. Visit megaphone.fm/adchoices

In this episode we trace how the ancient eye‑beam theory—claiming sight was an outward missile—held sway for centuries until Ibn al‑Haytham’s pinhole experiment in 12th‑century Cairo provided a reproducible refutation. We explore his experimental method, its impact on scientific methodology, and the long‑term shift toward empirical optics that paved the way for modern physics.

Learn more about your ad choices. Visit megaphone.fm/adchoices

The episode traces how Albert A. Michelson and Edward W. Morley's 1887 interferometer experiment—expecting to detect the elusive ether wind—returned a null result that upended prevailing physics, ultimately paving the way for Einstein’s theory of relativity. We explore the experiment’s design, its reception in the scientific community, and the chain reaction of experiments it inspired.

Learn more about your ad choices. Visit megaphone.fm/adchoices

In 1887, Michelson and Morley's null result shattered the century‑old ether hypothesis, forcing physicists to rethink light’s behavior and paving the way for Einstein’s special relativity. This episode traces that pivotal experiment, its technological roots in interferometry, and the broader ripple it created—from Lorentz transformations to GPS timing and LIGO’s gravitational‑wave detectors.

Learn more about your ad choices. Visit megaphone.fm/adchoices

In this episode, Josh dives into Einstein’s 1905 Brownian motion paper that finally proved atoms existed, tracing the path from Robert Brown’s pollen observations to Jean Perrin’s experimental confirmation. He explores how this breakthrough cemented statistical mechanics, reshaped measurement standards, and laid groundwork for modern materials science and nanotechnology. The story shows how a simple observation of random particle jitter can ripple through physics, engineering, and technology for over a century.

Learn more about your ad choices. Visit megaphone.fm/adchoices

This episode follows Rudolf Clausius as he transforms a practical problem in steam engine design into the concept of entropy—a cornerstone of modern thermodynamics, statistical mechanics, and even information theory. We trace his work from Carnot’s 1824 insights through Maxwell’s kinetic theory, examine how entropy became a predictive law, and explore its lasting influence on physics, engineering, and culture.

Learn more about your ad choices. Visit megaphone.fm/adchoices

From a market in Ionia to the birth of scientific reasoning, this episode follows Thales of Miletus as he uses observation and geometry to argue that all matter is made of water. We trace how his bold hypothesis challenged mythic explanations, sparked predictive astronomy, and laid the groundwork for modern experimental physics.

Learn more about your ad choices. Visit megaphone.fm/adchoices