Tuesday, February 10, 2015

Michelson built pre-digital Fourier computer

Pre-WWII analog computers were rare accomplishments, and I never heard of this one:
Pre-digital computer 'cranks out' Fourier Transforms
Boffins get a handle on pre-digital computer, restore it to working order

A group of American engineers have rescued and returned to operation a Fourier-Transform-calculating machine designed in the 19th century.

The machinery is an impressive reminder not only of what could be achieved in the pre-digital era, but also of the genius of its designer Albert Michelson, a name less-known to the general public than contemporaries like Albert Einstein.

Michelson's best-remembered achievements are contributions to setting a value to the velocity of light, and in collaboration with Edward Morley, constructing the famous Michaelson-Morley experiment which both disproved the theory of the aether and helped lay down the basis of interferometry.
Wikipedia says about the Michelson–Morley experiment
The extent to which the null result of the Michelson–Morley experiment influenced Einstein is disputed. Alluding to some statements of Einstein, many historians argue that it played no significant role in his path to special relativity,[A 24][A 25] while other statements of Einstein probably suggest that he was influenced by it.[A 26] In any case, the null result of the Michelson–Morley experiment helped the notion of the constancy of the speed of light gain widespread and rapid acceptance.[A 24]
And similarly about Michelson:
There has been some historical controversy over whether Albert Einstein was aware of the Michelson-Morley results when he developed his theory of special relativity, which pronounced the aether to be "superfluous." In a later interview, Einstein said of the Michelson-Morley experiment, "I was not conscious it had influenced me directly... I guess I just took it for granted that it was true.“[17] Regardless of Einstein's specific knowledge, the experiment is today considered the canonical experiment in regards to showing the lack of a detectable aether.[18][19]
The controversy is easy to explain. Einstein clearly explains in 1909 that the experiment was crucial to Lorentz and FitzGerald in developing the relativity principle, the constancy of the speed of light principle, and the Lorentz transformations. Einstein also said that it had no direct role in his own work, as he did not cite it and may not have realized how important it was until 1909.

Einstein said in 1921 that he knew about Michelson's work as a student (before 1905), and he has acknowledged basing his 1905 paper on Lorentz's 1895 paper, which stressed the importance of Michelson's work. He surely also read other papers of Lorentz and Poincare that emphasized Michelson-Morley. So yes, it is safe to say that he knew about the experiment in 1905 to the extent that he knew that relativity theory had been based on it.

Special relativity textbooks commonly explain the crucial importance of Michelson-Morley to the development of the theory, but it had little to do with Einstein's work. Einstein's main point was to postulate what Lorentz had proved, and he did not need to bother with Lorentz's experimental evidence. Einstein just assumed that Lorentz and Poincare were correct in their interpretation of Michelson-Morley.

4 comments:

  1. I've been reading a lot of Einstein's original papers recently, thinking his reputation was overblown. For the most part, his reputation was confirmed.

    Having said that, if physicists were to rank his 1905 work from most-to-least important they inevitably say (1) relativity (2) quantum mechanics (3) brownian motion/stat mech.

    I've personally come to the conclusion the exact opposite is true. The brownian motion/stat mech stuff was significantly more important than relativity, and if Einstein hadn't done that relativity work, we'd still have relativity just the same.

    The real disaster/problem wasn't Einstein or any of his work. It's was the myth of a super genius physicist overturning common sense and revolutionizing physics. This myth caused the best physicists in the 20th century to waist huge amounts of their potential "being the next Einstein". The damage to physics is un-calculable.

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  2. The Brownian motion paper was actually Einstein's most cited paper for a long time. It was useful for giving a estimate on the size of atoms.

    My book is titled "How Einstein Ruined Physics". As you say, the real problem was not him, but the myth that followed him. Maybe I should have titled it How the Einstein Myth Ruined Physics.

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  3. Contributions to science by scientists are almost always piecemeal. You can proclaim how much of a genius Newton was...except for that little part about his alchemy obsession. You can laud Copernicus for his 'contributions', except where he was wrong about some things. Same goes for pretty much anyone who ever contributed anything in any field of endeavor. The simple fact about discoveries and accomplishments is "They can't all be gems". Contributions are also always made by human beings, not marble paragons of perfection, so you have to accept the flaws of human character which helped define the people who made their mark.

    "Super genius" and "myth" hyperbole, nonsense, and other dreck, is the product of fawning celebrity worship and reporting industry. The same has been done with Richard Feynman, and more recently Stephen Hawking. One of these 'genius' gentleman admitted (during one his more lucid moments) his method was not 'mathematically valid', and the other admitted there was no such thing as what he had been mathematically onanizing over the last several decades.

    The worst thing that can happen to a anyone is having their name outgrow their ability and accomplishment. When this happens, the person becomes a perverse slave to a false idol of themselves.

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  4. Special Relativity is a breeze. All you have to do to make it simple to understand, is to discover it for yourself by analyzing "motion".

    I did it, so anyone should be able to do it. http://goo.gl/fz4R0I

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