Einstein’s relativity, and how it relates to gravity, explained in less than 10 minutes. This video uses a type of spacetime diagram invented by the physics author Lewis Carroll Epstein in his book "Relativity Visualized," with proper time on the y-axis (also representing the null geodesic that light takes in a vacuum). Epstein diagrams are more intuitive for the layperson than Minkowski diagrams, where the null geodesics are at 45° angles. Epstein's book is available at many libraries, as well as online at [ Ссылка ] .
The GPS & Relativity article referenced in the video is here: [ Ссылка ]
A different article, by NASA, is here: [ Ссылка ]
Questions are welcome, but fringe-science comments — like insisting that gravity can be explained as the Earth expanding, or buoyancy, or massive photons, or "electric universe" nonsense, etc. — are not (sorry). General relativity is one of the most battle-tested theories in physics, for over 100 years now. If you think you have a better theory, go ahead and evangelize that pseudoscience in your own video.
Thank you to my Patreon supporters [ Ссылка ]
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