In 1905, Albert Einstein published four studies that would change the laws of physics

Albert Einstein

Between March and September 1905, the German scientific journal "Annales der Physik" mailbox received four studies that would forever change the laws of physics and, ultimately, the conception of the reality of light, matter, time, and space.

The author was a 26-year-old Albert Einstein who, at the time, was working at the patent office in Berne (Switzerland). His career as a physicist had stalled after the rejection of his doctoral thesis, and his scientific passion had been relegated to his spare time and long idle hours in the office. However, this year was a miraculous one for Einstein with these four significant achievements:


On 9th June 1905, the journal published Einstein's dissertations on the photoelectric effect and the physics of light under the title "A Heuristic View of the Production and Transformation of Light". In it, he introduces the revolutionary idea that light is composed of both energy and quantifiable particles, which he called quanta (photons for history).

This conception that physical systems can behave as waves (energy) and particles (matter) would be the seed of one of the two pillars of modern physics: quantum mechanics.

Sixteen years later, this work on the photoelectric effect would take Albert Einstein to the pinnacle of science when, in 1921, he received the Nobel Prize in Physics.


The second study was published on 18 July under the title "On the motion required by the kinetic molecular theory of the heat of small particles suspended in a stationary liquid".

Einstein found in a physical phenomenon (Brownian motion) the empirical evidence for what many scientists thought at the time, that matter is composed of atoms. In attempting to explain this curious phenomenon, Einstein not only mathematically confirmed the existence of atoms and molecules but also inaugurated a new field in the study of physics, statistical physics.


The third study of that year was perhaps the most promising. It dealt with "The electrodynamics of moving bodies" and was published on 26th September 1905.

It was the condensation of Einstein's new physics into the well-known theory of special relativity, which preceded general relativity (which, in 1915, also included the influence of acceleration and gravity). Einstein postulated in this study that the speed of light is immutable, constant, and independent of the observer's motion. Therefore, with the exception of the constant speed of light, everything is relative, including time, distance, and mass.


Fórmula de Albert Einstein

On 21st November the last of the four studies was published with the question: "Does the inertia of a body depend on the energy it contains?"It is an epilogue to all the other studies in which the mathematical demonstration of specific relativity, and thus the proof of the equivalence between matter and energy, was condensed into the most famous formula in history: E = mc2.

Perhaps a new scientific revolution will come that will discard some of Einstein's ideas, but his method will live on forever.

Einstein's great merit was not to try to explain the results or the experiments themselves, but to elaborate a theory in which the experiment is the result and not the origin of a phenomenon.

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