What is Einstein's Equivalence Principle?

To check out the physics courses that I mentioned (many of which are free!) and to support this channel, go to https://brilliant.org/Sabine/ and create your Brilliant account. The first 200 will get 20% off the annual premium subscription. In this video I explain what the equivalence principle is, how it connects special relativity with general relativity, and why it's got nothing to do with the idea that the earth is flat. A good starting point for the reference that I mention at 7:39 is this paper: Nonequivalence of equivalence principles Eolo Di Casola, Stefano Liberati, Sebastiano Sonego Am. J. Phys. 83, 39 (2015) https://aapt.scitation.org/doi/10.111...