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A very great deal has been written about Einstein's discovery of the special theory of relativity. My goal in this work is to draw attention back to what was most important in the discovery, that it emerged from Einstein's sustained reflections on problems in electrodynamics. Once Maxwell's electrodynamics was in place, little could stop something like special relativity emerging. Until that electrodynamics was in place, no examination of clocks, their synchronization, agonies over what it really means to be simultaneous, and so on, could properly lead to special relativity. "Einstein's Investigations of Galilean Covariant Electrodynamics prior to 1905," Archive for History of Exact Sciences, 59 (2004), pp. 45-105. Download

"Einstein's Special Theory of Relativity and the Problems in the Electrodynamics of Moving Bodies that Led him to it." pp. 72-102 in Cambridge Companion to Einstein, M. Janssen and C. Lehner, eds., Cambridge University Press, 2014. Download.

Writing decades later in his Autobiographical Notes, Einstein recalled how his discovery of special relativity in 1905 was decisively furthered by his reading of the philosophical writings of Hume and Mach. Einstein's remark is intriguing and maddeningly brief. I try to pin down precisely what Einstein found so useful in the writings of Hume and Mach. I suggest that it was not a particular view of space and time but a theory of concepts.

"How Hume and Mach Helped Einstein Find Special Relativity," pp. 359-386 in M. Dickson and M. Domski, eds., Discourse on a New Method: Reinvigorating the Marriage of History and Philosophy of Science. Chicago and La Salle, IL: Open Court, 2010. Download
Einstein reported the importance to his discovery of special relativity of a famous thought experiment in which he chased a beam light and could thereby observe frozen light. This thought experiment is quite unlike others by Einstein since it is not clear why observing frozen light would be problematic. I suggest that the thought experiment recovers its cogency if we read it as an objection to an emission theory of light.

"Chasing the Light: Einstein's Most Famous Thought Experiment," prepared for Thought Experiments in Philosophy, Science and the Arts, eds., James Robert Brown, Mélanie Frappier and Letitia Meynell, Routledge. Download.

See also"Chasing the Light: Einstein's Most Famous Thought Experiment" in Goodies.
The final breakthrough for special relativity came some 5 to 6 weeks prior to the completion of the special relativity paper of 1905 when Einstein hit upon the relativity of simultaneity, a moment he called "The Step." Our default assumption is that he hit upon this result by reflecting on clocks and how we synchronize them with light signals. I suggest that we have no direct evidence for this assumption and that a more plausible pathway has him reading the result off the observation of stellar aberration and Fizeau's measurment of the speed of light in moving water.

See "Discovering the Relativity of Simultaneity: How did Einstein take "The Step"?" in Goodies or download as pdf.
In 1905, Einstein urged that high frequency light carries the distinctive signature of discreteness, so that its energy is distributed in spatially localized light quanta. The methods Einstein used to arrive at this startling result appear also in his other work of 1905 on Brownian motion and sugar solutions. There he routinely exploited the idea that the macroscopic, thermal properties of systems like ideal gases and dilute solutions carry a distinctive signature of atomic discreteness. Latest simplified account: "Einstein's Miraculous Argument of 1905: The Thermodynamic Grounding of Light Quanta" Download.

"Atoms, Entropy, Quanta: Einstein's Miraculous Argument of 1905," Studies in History and Philosophy of Modern Physics, 37 (2006), pp. 71-100. Download


"Atoms Entropy Quanta: Einstein's Statistical Physics of 1905" in Goodies.
In 2005 I spoke in several national and international conferences that celebrate Einstein's annus mirabilis of 1905.

Schedule and links to streaming video of two talks given in Bern, Switzerland.
Our urge to oversimplify has led to many myths about what powered Einstein's discoveries. Naive thinking? Capricious rule-breaking? Operational thinking? I correct some myths and try to give a more accurate picture of how Einstein made two discoveries: special relativity and the light quantum. ""How Einstein Did Not Discover," Physics in Perspective, 18 (2016), pp. 249-282. Download.