Da Vinci’s sketches, which were forgotten for decades, show triangles formed by sand-like particles pouring from a jar. These falling grains depicted experiments to show that gravity was a form of acceleration more than 400 years before Einstein did, a new study argues.
Newton knew it was acceleration too. It sounds to me like he was working with Newtonian gravity, not relativity. Nothing in the article touches on aspects of gravity outside of what Newton had figured out as far as I can tell.
I dunno. Everyone learns in high school that gravity causes acceleration. Da Vinci’s big idea here may have been realizing that. It seems possible to me that the common understanding at the time of these drawings was that things fell at a constant speed.
Interesting though, the article says that he had trouble proving it via experiment. That would indicate that he came up with the idea of acceleration due to gravity not from observation.
Anyways, none of this points to proto-relatvistic thinking.
