Leonardo da Vinci: what a genius! Analysis of his notes shows that, 100 years before Galileo, 200 years before Isaac Newton, he had begun to grasp the link between acceleration and gravity, the basis of all modern physics.
Hervé Poirier, editor-in-chief of the scientific magazine Epsiloon evokes today the pioneering research in fundamental sciences of Leonardo da Vinci (1452-1519).
franceinfo: Do we continue to discover how much Leonardo da Vinci was a pure scientific genius?
Herve Poirier: I’m not going to talk to you about flying machines, but about fundamental sciences. Because we have just realized that Leonardo da Vinci was the first to grasp the idea at the base of all modern physics.
It was professors from Caltech, an American university, who discovered his brilliant intuition: in the Codex Arundel, written around 1500, they noticed a series of small sketches, showing a sort of jar, which pours sorts of grains of sand, with triangles drawn around. And this is the handwritten phrase “Equation of Moti”, on one of the triangles, which tipped them off.
“Equation of Moti” ? What does it mean ?
It translates to “equivalence of movements”. The experiment actually consists of moving a jar horizontally, and watching the trajectory of the sand that pours out. Leonardo has managed to accelerate the jar, as fast as the sand falls. And he found that the grains then form a straight line inclined at 45°.
The equivalence in question is that between the horizontal acceleration of the jar and the vertical fall of the sand by gravity – with the line at 45°, it makes a triangle. Leonardo thus identifies here, acceleration and gravity. And that is visionary, even revolutionary thought. It will be necessary to wait more than 400 years for Galileo, Newton, then Einstein, to follow this thought.
Leonardo da Vinci would therefore be the precursor of Einstein here?
Yes ! Einstein’s greatest idea, “the happiest of her life”, as he will say, it is this equivalence between gravity and acceleration. Einstein built his theory of general relativity on this intuition. Imagine that you are going up in an elevator: you feel heavy when it starts to accelerate, and light when it decelerates.
Acceleration is like gravity; gravity is like acceleration. Going to the end of this equivalence, it is the very complex relativistic equations that arrive, which perfectly describe the fall of the apples, the race of the planets or the origin of the cosmos.
“Equation of Moti” : Leonardo’s math remained approximate, but the most important thought in the whole history of physics was already there, in 1500, in this codex. What a genius!