1905, The Silent Revolution: When Einstein Rewrote the Laws of Nature

1905: An Incredible Year in the History of Physics

In 1905, Albert Einstein (1879-1955), then a simple technical employee at the Patent Office in Bern, published five fundamental articles in the journal Annalen der Physik. At just 26 years old, he revolutionized theoretical physics on several fronts: the quantum nature of light, Brownian motion, the relativity of time and space, and the revolutionary idea of an equivalence between mass and energy, initially formulated as: \(\Delta E = \Delta m \cdot c^2\).
These four articles are truly considered "revolutionary." The fifth is his doctoral thesis on molecular dimensions, which has scientific value but limited impact.

The year 1905 is known as the Annus Mirabilis — the miraculous year — as the impact of his ideas redefined the foundations of modern physics.

The Five Revolutionary Articles

Here are the five major articles published by Einstein in 1905:

• March 17, 1905 — A Heuristic Point of View Concerning the Production and Transformation of Light: Einstein introduces the hypothesis of light quanta (photons), explaining the photoelectric effect and laying the foundations of quantum mechanics.
• April 30, 1905 — A New Determination of Molecular Dimensions: His doctoral thesis, where he determines the size of molecules from viscosity and diffusion.
• May 11, 1905 — On the Movement of Small Particles Suspended in a Stationary Liquid: He provides a theoretical description of Brownian motion, confirming the existence of atoms.
• June 30, 1905 — On the Electrodynamics of Moving Bodies: He lays the foundations of special relativity, rejecting the ether and introducing the constancy of the speed of light for all observers.
• September 27, 1905 — Does the Inertia of a Body Depend Upon Its Energy Content?: In this article, Einstein deduces that if a body loses energy \(\mathcal{L}\), its mass decreases by \(\Delta m = \dfrac{\mathcal{L}}{c^2}\). He concludes that energy and mass are related, thus laying the foundations for the mass-energy equivalence, which would later be generalized in 1907 as \( E_0 = mc^2 \) and in 1911 as \( E = mc^2 \).

Impact on Modern Physics

These five publications cover three major areas: quantum physics, statistical physics, and relativity. Together, they trigger a paradigm shift:

• The concept of the photon paves the way for the quantum theory of light, anticipating the work of Max Planck (1858-1947), Niels Bohr (1885-1962), and later Werner Heisenberg (1901-1976) and Erwin Schrödinger (1887-1961).
• The modeling of Brownian motion provides irrefutable physical evidence of the existence of atoms and molecules, which some scientists still questioned at the time.
• Einstein's theory of special relativity eliminates the idea that events occur at the same absolute moment for everyone; space and time depend on the motion of each observer.

Albert Einstein: An Isolated but Visionary Genius

At that time, Einstein, without university affiliation, laboratory, mentor, or physicist colleagues, single-handedly redefined the theoretical foundations of physics. This highlights his prodigious intelligence and the heuristic power of his physical intuition, capable of transcending the experimental limits of his time.

The year 1905 marks Einstein's entry into the history of science. It constitutes a turning point where classical physics, based on the laws of Isaac Newton (1642-1727) and James Clerk Maxwell (1831-1879), gives way to a new conceptual architecture where relativity, quantum mechanics, and statistical physics coexist. These publications are not incremental improvements but major epistemological breaks that open the scientific 20th century. In a single year, Albert Einstein forever transformed our understanding of the world.

Summary Table of the Four Major Articles Published in 1905

These four articles are now considered revolutionary.