.jpg)
The annus mirabilis papers (from Latin annus mīrābilis) are the four papers that Albert Einstein published in Annalen der Physik, a scientific journal, in 1905; 119 years ago.
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 all four of these papers in a single year, 1905 is called his annus mirabilis (miracle year).
The first paper explained the photoelectric effect; The second paper explained Brownian motion, the third paper introduced Einstein's theory of special relativity, and the fourth, a consequence of the theory of special relativity, developed the principle of mass–energy equivalence.
These four papers, together with quantum mechanics and Einstein's later theory of general relativity, are the foundation of modern physics.
Einstein's Zur Elektrodynamik bewegter Körper (On the Electrodynamics of Moving Bodies), his third paper that year, was received on 30 June and published 26 September. 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'.
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), and which had been crucial for the development of the Lorentz transformations and the principle of relativity.
The speed of light is fixed, and thus not relative to the movement of the observer. This was impossible under Newtonian classical mechanics.
It had previously been proposed, by George FitzGerald in 1889 and by Lorentz in 1892, independently of each other, that the Michelson-Morley result could be accounted for if moving bodies were contracted in the direction of their motion. Some of the paper's core equations, the Lorentz transforms, had been published by Joseph Larmor (1897, 1900), Hendrik Lorentz (1895, 1899, 1904) and Henri Poincaré (1905), in a development of Lorentz's 1904 paper. Einstein's presentation differed from the explanations given by FitzGerald, Larmor, and Lorentz, but was similar in many respects to the formulation by Poincaré (1905).
His explanation arises from two axioms. The first is Galileo's idea that the laws of nature should be the same for all observers that move with constant speed relative to each other.
The theory, now called the special theory of relativity, distinguishes it from his later general theory of relativity, which considers all observers to be equivalent.
Acknowledging the role of Max Planck in the early dissemination of his ideas, Einstein wrote in 1913 The attention that this theory so quickly received from colleagues is surely to be ascribed in large part to the resoluteness and warmth with which he [Planck] intervened for this theory.
In addition, the spacetime formulation by Hermann Minkowski in 1907 was influential in gaining widespread acceptance. Also, and most importantly, the theory was supported by an ever-increasing body of confirmatory experimental evidence.
More information: Archive
No comments:
Post a Comment