Einstein wrote five research papers in 1905, which laid the foundation for Modern Physics. Coinciding with the centenary of Einstein’s “Miraculous Year”, the United Nation has declared 2005 as the International Year of Physics.
Credit: American Institute of Physics
Albert Einstein was awarded the Nobel Prize for Physics in 1921 for "for his services to Theoretical Physics and especially for his discovery of the law of the photoelectric effect". Sir Isaac Newton wrote to his bitter rival, Robert Hooke, "If I have seen farther, it is by standing on the shoulders of giants". This is how breakthroughs in science are achieved, when giants stand on the shoulders of giants! Einstein was extremely smart to realize many important experimental results of his time. In this page we list the great experiments of 19th and 20th centuries that shaped what is known today as Modern Physics. Each listing is linked to a detailed site.
Important Experiments in Physics
(Nemiroff, R. J., American Journal of Physics, 61, 619 (1993))
Great spirits have always encountered violent opposition from mediocre minds. - Einstein
The 1905 Papers
1. "A New Determination of Molecular
Dimensions" (Einstein's doctoral dissertation) (30 April 1905)
Buchdruckerei K. J. Wyss,
This is Einstein's doctoral
dissertation, submitted to the
2. "On the motion of small particles suspended in liquids at rest required by the molecular-kinetic theory of heat." (Brownian motion paper) (May 1905; received 11 May 1905), Annalen der Physik, 17(1905), pp. 549-560.
In this paper Einstein relates the random motion small particles suspended in water to Brownian motion and develops the kinetic theory of heat. The prediction is a powerful test of the truth of the kinetic theory of heat. It provides a way to estimate Avogadro's number.
3. "On the electrodynamics of moving
bodies" (special relativity) (June 1905; received 30 June 1905)
Annalen der Physik, 17(1905), pp. 891-921.
In this paper, Einstein develops the special theory of relativity. The absence of ether was already demonstrated by the Michelson-Morley Experiment. The result of this experiment was fully exploited in developing the theoretical idea here. Einstein shows that Maxwell-Lorentz electrodynamics has in fact always obeyed a principle of relativity of inertial motion. This is a classic example of how a negative result leads to profound idea.
Annalen der Physik, 18(1905), pp. 639-41.
A brief follow-up to the special relativity paper that derives famous relation E = mc2.
Annalen der Physik, 17(1905), pp. 132-148.
In this paper, Einstein gives his famous theory of Photoelectric effect. He looks at the thermodynamic properties of high frequency heat radiation and finds that this radiation behaves just like a collection of many spatially localized "quanta" of energy of magnitude hf, where h is Planck's constant and f is frequency. This was a revolutionary idea leading to his Noble Prize.
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