Third in the Top Eleven is Sir Isaac Newton, who squeaks in with two nominations for two different experiments.
Who: Isaac Newton (1642-1727), famous English physicist, mathematician, alchemist, Master of the Mint, and Neal Stephenson character.
When: Newton was secretive and reluctant to publish anything, so it’s sort of hard to assign dates. I’m going with “About 1700.”
What: Newton pretty much kicked off modern science, so you could go on for a long time about his various accomplishments, but he was cited for two specific experiments: splitting white light with a prism, and measuring the motion of fluids.
People had known for a while that a prism could be used to divide white light into beams of various colors, but it was unclear whether the colors were inherent in the light, or something added by the prism. Newton’s big achievement was devising an experiment that showed that the colors are part of the light itself, by showing that the light could be re-combined to form white light again. This was part of a larger set of meticulous and obsessively detailed experiments on optics, that included poking at the back of his own retina with a knife, to see what would happen.
As for the fluid stuff, he carried out a number of similarly meticulous experiments on the motions of vortices in fluids in order to disprove the main competitor to his theory of gravitation as an explanation for the orbits of the planets. The other main theory was that of Descartes, who believed that the planets were carried around the Sun by some sort of vortices. Newton carefully measured the motion of particles in circulating fluids, in order to show that it was impossible to reproduce the observed motions of the planets using fluid transport as a mechanism (in particular, the orbital periods of the planets don’t scale in the right way as you move out from the Sun. If you set up a vortex that matches the motion of the Earth, it can’t give you the right speed for Jupiter). Newton’s proposed Law of Universal Graviation does reproduce the observed behavior.
Why It’s Important: In both cases, the experiments are more important on a sort of meta-scientific level than they are in their own right (though the splitting of light was a big deal). What’s really important are the ideas of developing clever experimental techniques to settle difficult problems, and of using small-scale systems to as models for large-scale physics.
Reasons to Vote for Him:: Galileo may have done the first measurements that are recognizable as modern science, by Newton really set the standard. Also, the Principia is such a towering achievement in theoretical physics, that he probably deserves a few sympathy votes. Inspired a pretty cool Pink Floyd album cover.
Reasons to Vote Against Him: These aren’t really on the same order of importance as the other experimental results. Also, he was a pretty unpleasant person, and kind of a nut, really.