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Sun Sep 26, 2021, 09:51 AM

On this day, September 26, 1905, Einstein's "Zur Elektrodynamik bewegter Korper" was published.

Well, isn't that special.

Annus Mirabilis papers

Einstein in 1904 or 1905, about the time he wrote the Annus Mirabilis papers

The Annus mirabilis papers ( from Latin annus mīrābilis, "miracle year" ) are the four papers that Albert Einstein published in Annalen der Physik (Annals of Physics), a scientific journal, in 1905. These four papers were major contributions to the foundation of modern physics. They revolutionized science's understanding of the fundamental concepts of space, time, mass, and energy. Because Einstein published these remarkable papers in a single year, 1905 is called his annus mirabilis (miracle year in English or Wunderjahr in German).

The first paper explained the photoelectric effect, which was the only specific discovery mentioned in the citation awarding Einstein the Nobel Prize in Physics. The second paper explained Brownian motion, which led reluctant physicists to accept the existence of atoms. The third paper introduced Einstein's theory of special relativity. The fourth, a consequence of the theory of special relativity, developed the principle of mass-energy equivalence, expressed in the famous equation E = mc^2 and which led to the discovery and use of atomic energy. These four papers, together with quantum mechanics and Einstein's later theory of general relativity, are the foundation of modern physics.


Special relativity

Main article: Special relativity

Einstein's paper in the original German, "Zur Elektrodynamik bewegter Körper", Annalen der Physik, September 26, 1905.

Einstein's "Zur Elektrodynamik bewegter Körper" ("On the Electrodynamics of Moving Bodies), his third paper that year, was received on June 30 and published September 26. It reconciles Maxwell's equations for electricity and magnetism with the laws of mechanics by introducing major changes to mechanics close to the speed of light. This later became known as Einstein's special theory of relativity.

The paper mentions the names of only five other scientists: Isaac Newton, James Clerk Maxwell, Heinrich Hertz, Christian Doppler, and Hendrik Lorentz. It does not have any references to any other publications. Many of the ideas had already been published by others, as detailed in history of special relativity and relativity priority dispute. However, Einstein's paper introduces a theory of time, distance, mass, and energy that was consistent with electromagnetism, but omitted the force of gravity.

At the time, it was known that Maxwell's equations, when applied to moving bodies, led to asymmetries (moving magnet and conductor problem), and that it had not been possible to discover any motion of the Earth relative to the 'light medium' (i.e. aether). Einstein puts forward two postulates to explain these observations. First, he applies the principle of relativity, which states that the laws of physics remain the same for any non-accelerating frame of reference (called an inertial reference frame), to the laws of electrodynamics and optics as well as mechanics. In the second postulate, Einstein proposes that the speed of light has the same value in all frames of reference, independent of the state of motion of the emitting body.

Special relativity is thus consistent with the result of the Michelson–Morley experiment, which had not detected a medium of conductance (or aether) for light waves unlike other known waves that require a medium (such as water or air).


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Reply On this day, September 26, 1905, Einstein's "Zur Elektrodynamik bewegter Korper" was published. (Original post)
mahatmakanejeeves Sep 2021 OP
SCantiGOP Sep 2021 #1
Igel Sep 2021 #2

Response to mahatmakanejeeves (Original post)

Sun Sep 26, 2021, 10:40 AM

1. Amazing that he could be that smart

and still possess wit and a sense of social responsibility.
It’s a good thing that he and most of the other physicists of the day were Jewish, or the Nazis would have likely had the atomic bomb before we did.

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Response to mahatmakanejeeves (Original post)

Sun Sep 26, 2021, 03:09 PM

2. I used to be annoyed at the lack of references to prior work.

Then one day as I was reading something and it just gave the reference as some guy's name followed by KZ, it dawned on me.

For that field there were maybe 3 journals and a few dozen books published by 1890. If you were working in the field, you'd be familiar with them all. By adding KZ the writer was just saying which of the three journals the relevant work by that particular guy was published in. Went to the university library (instead of my personal library, as a scholar in 1895 would have), pulled the copies for the previous 10 years off the shelf, and found the article.

Suddenly my irritation vanished. Now, I'd need to cite each thing because people aren't familiar with that literature; and for modern literature, with scores of journals and hundreds of researchers, you can't keep up with everything. Back then ...

It's nice that the 3rd word in the article is "Maxwell" though.

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