PBS Space Time Season 2020 Episode 17 How Luminiferous Aether Led to Relativity

PBS Space Time is a YouTube channel dedicated exclusively to exploring the world of physics. Hosted by Gabe Perez-Giz, the show combines humor, wit, and expert-level knowledge to make complex scientific ideas accessible to viewers of all backgrounds. In season 2020, episode 17, How Luminiferous Aether Led to Relativity, the host takes viewers on a journey through the fascinating history of 19th-century physics, exploring the development of aether theory and its eventual downfall at the hands of Einstein's theory of relativity.

The episode begins by explaining the concept of aether, a theoretical medium believed to permeate all of space and provide a basis for the transmission of light waves. Scientists in the 19th century were convinced that aether must exist because light can travel through a vacuum, and they believed that it needed a medium to carry it. Thus, they searched for aether like a sailor searching for the ocean floor. They believed that aether had a specific definition, as it had to also act as a universal reference frame, a space-time grid by which all of the universe could be measured.

The episode delves into the experimental evidence that supported the existence of aether. Specifically, it explores the Michelson-Morley experiment, which sought to measure the relative motion of the Earth through the aether by measuring the speed of light in various directions. The experiment failed to show any evidence of aether, however, suggesting that the medium either didn't exist or that the Earth was somehow at rest within it.

As a result of the Michelson-Morley experiment, scientists began to question the existence of aether. However, it wasn't until Einstein arrived on the scene that a new theory of light propagation emerged. The episode explores the fundamental ideas behind relativity, which essentially eliminated the need for aether entirely. Einstein's theory proposed that the laws of physics must be the same for all observers, regardless of their relative motion to one another. The theory of relativity gave us the speed of light as a universal barrier, allowing us to understand that the faster you travel through space, the slower you will experience time. It also redefined space and time into a single four-dimensional framework, a new space-time grid that eliminated the aether Universal ruler.

Overall, How Luminiferous Aether Led to Relativity is a fascinating episode that explores the history of physics and the development of two major theories that continue to shape our understanding of the universe today. It provides viewers with an in-depth look at the scientific process, showing how theories evolve and change in the face of new evidence and new ideas. Whether you're a science buff or just curious about how the world works, this episode is sure to educate and entertain. So, buckle up and get ready for a thrilling ride through physics history as you discover how luminiferous aether led to relativity!