The history of electromagnetism is truly bizarre when you think about it. The theory was essentially 100% complete in 1873 in A Treatise on Electricity and Magnetism. Well, supposedly complete - as nobody could really understand its content fully, not even the author. Maxwell introduced the displacement current as a small technical fix, but failed to realize it could generate E&M waves. The reanalysis of the book took physicists 10 to 20 years. Pupin traveled from US to Cambridge because he wanted to ask the question "WTF is the book?" personally to Maxwell. The young Heaviside said understanding this book was his life goal (realized during 1880-1890). During this period, nobody really knows for sure that E&M waves exist. Even after Hertz demostrated E&M waves, physicists all believed it was a short-range effect like light. Then in 1895 Marconi discovered a practical longwave ratio transmitter by random tinkering. After he heard telegraph transmitters are grounded, he tried it too, accidentally inventing the monopole antenna by sheer luck (and also made it the first case of "cargo cult grounding" in RF electronics, today still practiced by many technicians that should knew better). Except that it actually worked for him spectacularly because of a quirk of the Earth's atmosphere. Physicists had absolutely no idea about it and the explanation at that time by physics guru Sommerfeld (the Zenneck surface wave solution to Maxwell's equation) was completely wrong. In 1905, there was already special relativity but still little understanding about antennas and waveguides in general. Some people actually argued that special relativity made E&M simpler... #electronics
@icedquinn Ah yeah, Faraday, single-handedly founded the entirety of electromagnetism by trial and error experiments without knowing anything about math.
@icedquinn imagine discovering new physics today by a tinkerer who doesn't even know how to solve an ordinary differential equations. Faraday did the equivalent of that.
@niconiconi :ablobcatnod: he did learn some things from the books if i recall, but he wasn't formally trained.
sometimes fun to remind academia that they live downstream of reality. there's been an eternal strife between the practical experimenters and the academics because of that.
@icedquinn The early history of electrical engineering is an oddity in the sense that it was almost completely dominated by experimenters, technicians, and industrialists. Many important techniques were invented first in the industry to solve practical problems, such as precision metrology because they moved back to physics labs.
There's still an upper limit without math. When Lord Kelvin derived the RC transmission line theory and said the transatlanic cable was doomed, Wildman Whitehouse, a competent experimenter by trade, didn't believe him because he didn't understand partial differential equations. When Heaviside derived the RLCG transmission line and invented inductive loading, his work was suppressed by Preece who was the government engineer and also an experienced experimenter by trade, because he too didn't understand differential equations. Lee de Forest invented the triode amplifier by sheer luck and self-titled him "the father of radio", but this guy is basically today's equivalent of an internet startup fraud. When Edwin Armstrong correctly pointed out how his radio worked he too tried to use his authority to suppress it. The Forest-Armstrong affair was likely a factor that led to his eventual suicide.
@niconiconi maxwell wrote his equations in quaternions, too, but were suppressed because people were like ew no imaginary numbers.
i mean i kind of prefer geometric algebra to quaternions sure but its still weird. i've since seen some other fringe electrical engineers nod that actually electricity does exist in a pseudo four dimensional waveform and we're all just kind of pretending it doesn't because nobody likes the math.
@icedquinn His work was not really suppressed, just too difficult to understand to make sense of anything out of it for 90% of the physicists. Freeman Dyson also remarked that he was also being too modest about his E&M theory, and only described it as the new theory that he prefers (in comparison to the old Newtonian "molecular vortex" based theory) at that time. Dyson said if he promoted his own view harder, it may have accelerated the progress by 20 years. http://www.damtp.cam.ac.uk/user/tong/em/dyson.pdf
Also, Quaternion was the standard tool but Maxwell himself didn't use it in particular in the Treatise, what the book did contain was 10-20+ equations for a bunch of different electromagnetic things known at that time, and they were all in Cartesian coordinates for each X/Y/Z polarization. Other people already used quaternions in E&M, including reanalyzing Maxwell, but many physicists found quaternions were completely devoided of physics intuition and it was likely a reason why Maxwell's theory was so difficult to understand.
Heaviside reanalyzed the theory in term of vector calculus and simplified into 2 for E&M waves and is crucial for making the theory understandable today. Heaviside told his readers about this life story in one book about E&M:
More than a third part of a century ago, in the library of an ancient town, a youth might have been seen tasting the sweets of knowledge to see how he liked them. He was of somewhat unprepossessing appearance, carrying on his brow the heavy scowl that the "mostly-fools" consider to mark a scoundrel. In his father's house were not many books, so it was like a journey into strange lands to go book-tasting. Some books were poison; theology and metaphysics in particular they were shut up with a bang. But scientific works were better; there was some sense in seeking the laws of God by observation and experiment, and by reasoning founded thereon. Some very big books bearing stupendous names, such as Newton, Laplace, and so on, attracted his attention. On examination, he concluded that he could understand them if he tried, though the limited capacity of his head made their study undesirable. But what was Quaternions ? An extraordinary name! Three books ; two very big volumes called Elements, and a smaller fat one called Lectures. What could quaternions be? He took those books home and tried to find out. He succeeded after some trouble, but found some of the properties of vectors professedly proved were wholly incomprehensible. How could the square of a vector be negative? And Hamilton was so positive about it. After the deepest research, the youth gave it up, and returned the books. He then died, and was never seen again.
@niconiconi apparently the math was onerous to do without mechanical calculators. and there's no real intuitive way to visualize imaginary numbers.
i know the people trying to get quaternions replaced with geometric algebra pushed that heavily. the way operations are derived are fairly easy to explain in GA, as well as individual steps of wedge operators being something a human can see, whereas when i was faced with trying to reason about quats without math training it was just fucking magic numbers doing formulas.
@niconiconi i read eric dollards thing on using versor algebra to explain electricity going through its phase cycles but i don't really understand the significance of that at the moment :blobcatlaydown:
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