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Kepler's discovery of elliptical orbits has long been a favorite story and demonstrative example: Copernicus is now hailed as a visionary who's theory was rejected out of dogmatic belief in the planets orbiting Earth. However his proposal was rejected on the basis that it is a poorer match of the data than the current models. It wasn't until Kepler found his elliptical orbits that the heliocentric model produced better results. This is close to an error commonly seen in science (mostly by amateur scientists), where people propose an overly simple model that just doesn't match the data, and when they are rejected on this basis they rail against science for not seeing their vision. It's an important lesson in pride, and knowing that while simplicity is beautiful and should be sought, it must match the data and have predictive power to be an explanation.I knew this story from a history of science class, but I never knew the details of the math until your videos. Thank you very much.This is a terrific series. Every previous telling of Kepler's story I've heard (and I've heard/read a lot!) is basically "He had this nested-platonic-solids idea which was wrong and amusing, then eventually he got all of Tycho's data and messed around and finally hit on ellipses." I'd never heard of his "extremely accurate but actually wrong" model, or what propelled him on to the correct one.This video demonstrates what a genius Kepler was.I like the phrase: ?? what it really looks like to do modern science. In stead of having phylosofical debates about how nature should work, they turned to methodical observation and messy experimentation.?That reminded me of the standard model of particles, and how theories like string theory - no observations, no experiments, just mathematical debates -paralyze science for decades.
Let's explore how a tiny lab accident in 1887 (by Heinrich Hertz) unlocked the quantum revolution. This is a story of how Philipp Lenard, Max Planck, and Robert Millikan helped Einstein discover the quantum nature of light. Chapters: 00:00 The tiny lab accident02:30 The brilliant experiment with electrons05:58 The shocking discovery07:27 Lenard's trigger hypothesis09:03 Trigger hypothesis is in trouble10:13 A revolutionary tool11:40 Max Planck's act of despair (using water analogy)16:14 Einstein's epiphany21:13 Challenges to Einstein's revolutionary idea23:59 The last straw or was it? 29:58 The writing on the wall
Millikan's notebooks are, frankly, less than candid. Fortunately his underlying belief in the quantised nature of charge turns out to be true, but his brilliant experimental "proof" would not have stood up in a court!
Because it works, and nobody has found a particle with a fractional charge.
Fair enough if you have a good idea of what the signal should look like, or what causes the deviations, but Millikan rather assumed quantisation of charge and just ignored any results that didn't fit the hypothesis. That's common practice in economics, politics, religion, and every other form of quackery, but it's frowned upon in physics.
//www.youtube.com/watch?v=r7k5G_6yzDwHow Hert'z Mistake Led Einstein to Quantum Physics!QuoteLet's explore how a tiny lab accident in 1887 (by Heinrich Hertz) unlocked the quantum revolution. This is a story of how Philipp Lenard, Max Planck, and Robert Millikan helped Einstein discover the quantum nature of light. Chapters: 00:00 The tiny lab accident02:30 The brilliant experiment with electrons05:58 The shocking discovery07:27 Lenard's trigger hypothesis09:03 Trigger hypothesis is in trouble10:13 A revolutionary tool11:40 Max Planck's act of despair (using water analogy)16:14 Einstein's epiphany21:13 Challenges to Einstein's revolutionary idea23:59 The last straw or was it? 29:58 The writing on the wall
Did he find a case where the electric charge wasn't quantized?
Quote from: hamdani yusuf on 07/08/2024 14:24:44Did he find a case where the electric charge wasn't quantized?No, he recorded measurements that were not consistent with quantisation, but did not report them.Although the experiment was arguably a stroke of genius, his performance really wasn't. Just like me trying to play a Bach sonata - but nobody would base an entire theory of baroque music on my fumbled fingering of it!
How do you know about them if they were not reported?
What caused the inconsistency with quantization?
By comparing his laboratory notebooks with his published papers.
Random experimental errors.
So, his laboratory notebooks were eventually published.
Quote from: Origin on 20/03/2024 13:54:29That frequency is the rate at which the magnetic and electric field of the photon oscillate from a maximum to a minimum and back to a maximum.FYI, circularly polarized light has a constant amplitude of electric field when propagating as a plane wave. Only the orientation rotates.
That frequency is the rate at which the magnetic and electric field of the photon oscillate from a maximum to a minimum and back to a maximum.
Really? Wave propagation has nothing to do with QM - it's purely continuum mathematics.
All light appears to be quantised as we don't have a means of generating continuous em waves at such high frequencies.We can discriminate quanta by time of arrival if the intensity is low enough.