This is a letter, written by Albert Einstein, in which he explains the details of a now-famous test of the theory of relativity—an experiment that involves measuring how the Sun's gravity alters the path of starlight traveling towards Earth.
There's a couple of important things to bring up here. First, this sheet of paper is a really handy reminder to test everything—even the work of geniuses. This test had to be performed during a full solar eclipse. Besides that stipulation there was also, you know, the existence of World War I getting in the way. So while Einstein wrote this letter in 1913, nobody carried out and documented the test until 1919.
And that wasn't the end of it. This is the fun thing about science. We might think Einstein is an awfully smart guy. And we might trust the character of Sir Arthur Eddington, who performed the 1919 test. But a hypothesis and a single confirmation of that hypothesis, is not enough to prove even Einstein right. Einstein's theory of relativity rests on several different tests, each carried out by multiple teams, over many years, using increasingly accurate tools. As late as the 1960s and 1970s, this test was still being done with the understanding that Einstein's predictions hadn't yet been verified.
Also very important: Understanding what the hell Einstein's theory of relativity is all about to begin with. For a great in-a-nutshell explanation that puts Einstein into historical context while actually making sense, I recommend checking out the short videos at Einstein Light. Produced by the University of New South Wales, this site combines helpful visuals, clear explanations, and lots of links (so you can take it deeper if you want).
Learn more about Einstein and relativity at Einstein Light.
From the Albert Einstein Archives. Via Paul Halpern.
Researchers successfully taught rats how to drive small cars in the pursuit of Froot Loops cereal. Video below. Psychologist Kelly Lambert and her colleagues at the University of Richmond conducted the experiment to gain insight into animal cognition. Learning to drive also lowered the rats’ stress as measured by hormone levels. From New Scientist: They […]
Russian scientist Denis Rebrikov claims that he’s begun a gene-editing process to eventually enable couples who both carry a specific genetic mutation that causes deafness to birth children who can hear. Rebrikov formerly announced his effort to use the CRISPR tool for gene editing to create babies resistant to HIV. From Nature: In his e-mail […]
Caltech theoretical physicist Sean Carroll, author of Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime, explains the concept of a “dimensions” at five different levels of complexity. Dr. Carroll sure has a big brane.
If you’re just jumping into app development for Apple’s devices, you’ve picked a heady time. The new iOS 13 has a ton of new features: A versatile SwiftUI language, a boosted role for Siri and a more robust Photos app, just to name a few. And if you’re making the transition from iOS 12? Get […]
Most people don’t spare a lot of thought on the potting for their plants. Perhaps something with a color that matches the walls, but that’s as far as it goes. After all, the plants don’t care what they’re wearing. Do they? Actually, they might. As eye-catching as the AIRSAI Floating Bonsai Plant Pot is, its […]
With the gains real estate has made over stocks in the past 25 years, it’s easy to see why the rich constantly use it to expand their wealth. What’s slightly less obvious is why only the rich seem to ever break into real estate investment. There are a lot of reasons, but a couple of […]