1687 Classical Era
Isaac Newton
Philosophiæ Naturalis Principia Mathematica Mathematical Principles of Natural Philosophy Royal Society
The most important scientific book ever written. Newton formulated three laws of motion and universal gravitation, unifying terrestrial and celestial mechanics under one mathematical framework for the first time. He invented the calculus needed to do it and set the standard for quantitative science for over two hundred years.
1897 Atomic Age 🏆 Nobel Prize in Physics
J. J. Thomson
Cathode Rays Philosophical Magazine, 44, 293–316
Thomson's careful cathode ray experiments proved that the rays are streams of negatively charged particles far lighter than any atom — what we now call electrons. This was the discovery of the first subatomic particle, ending the 2,400-year-old idea that atoms are indivisible, and opening the entire field of particle physics.
1905 Relativity
Albert Einstein
Zur Elektrodynamik bewegter Körper On the Electrodynamics of Moving Bodies Annalen der Physik, 17, 891–921
Einstein's special relativity paper abolished the luminiferous ether and showed that the speed of light is the same for all observers. Starting from just two postulates — the laws of physics are the same in all inertial frames, and c is constant — Einstein derived time dilation, length contraction, and the relativity of simultaneity. It fundamentally changed our understanding of space and time.
1905 Relativity
Albert Einstein
Ist die Trägheit eines Körpers von seinem Energieinhalt abhängig? Does the Inertia of a Body Depend Upon Its Energy Content? Annalen der Physik, 18, 639–641
In just three pages, Einstein derived the most famous equation in science: E = mc². He showed that mass and energy are equivalent and interconvertible, with the conversion factor being the square of the speed of light. This insight underpins nuclear energy, nuclear weapons, particle accelerators, and PET scanners — essentially all of modern nuclear and particle physics.
1905 Atomic Age
Albert Einstein
Über die von der molekularkinetischen Theorie der Wärme geforderte Bewegung von in ruhenden Flüssigkeiten suspendierten Teilchen On the Movement of Small Particles Suspended in Stationary Liquids Required by the Molecular-Kinetic Theory of Heat Annalen der Physik, 17, 549–560
Einstein derived a precise mathematical formula predicting how particles suspended in a fluid should jiggle randomly due to collisions with individual molecules — Brownian motion. This was the first rigorous quantitative proof that atoms and molecules are real physical objects, not merely a convenient calculational fiction. Jean Perrin's 1908 experiments confirmed Einstein's predictions exactly, finally settling the 2,000-year-old debate over atomic existence and earning Perrin the 1926 Nobel Prize.
1905 Atomic Age 🏆 Nobel Prize in Physics
Albert Einstein
Über einen die Erzeugung und Verwandlung des Lichtes betreffenden heuristischen Gesichtspunkt On a Heuristic Point of View Concerning the Production and Transformation of Light Annalen der Physik, 17, 132–148
Einstein proposed that light is composed of discrete energy packets — quanta, now called photons — each carrying energy E = hf. This explained the photoelectric effect: why light below a threshold frequency ejects no electrons regardless of intensity, because individual photons carry insufficient energy. Classical wave theory had no answer. This paper launched quantum optics, the photon concept, and every photon-based technology from solar cells to CCDs. It won Einstein his only Nobel Prize — not for relativity.
1911 Atomic Age 🏆 Nobel Prize in Chemistry
Ernest Rutherford
The Scattering of α and β Particles by Matter and the Structure of the Atom Philosophical Magazine, 21, 669–688
Analyzing the famous gold foil experiments by Geiger and Marsden, Rutherford showed that most of an atom is empty space and that its positive charge and most of its mass are concentrated in a tiny central nucleus. This demolished Thomson's "plum pudding" model and established the nuclear model of the atom that we still use today.
1913 Atomic Age 🏆 Nobel Prize in Physics
Niels Bohr
On the Constitution of Atoms and Molecules Philosophical Magazine, 26, 1–25
Bohr introduced quantized electron orbits into the nuclear model of the atom, explaining why electrons don't spiral into the nucleus and why atoms emit only specific wavelengths of light. He derived the Rydberg formula for hydrogen from first principles. This was the first successful quantum model of the atom and triggered the quantum revolution of the 1920s.
1916 Relativity 🏆 Nobel Prize in Physics
Albert Einstein
Die Grundlage der allgemeinen Relativitätstheorie The Foundation of General Relativity Annalen der Physik, 49, 769–822
Einstein's general theory of relativity recast gravity not as a force but as the curvature of spacetime caused by mass and energy. The Einstein field equations govern everything from GPS satellites to black holes to the expansion of the universe. Every major prediction — gravitational waves, gravitational lensing, black holes, gravitational redshift — has since been confirmed experimentally.
1926 Quantum Era 🏆 Nobel Prize in Physics
Erwin Schrödinger
Quantisierung als Eigenwertproblem Quantization as an Eigenvalue Problem Annalen der Physik, 79, 361–376
Schrödinger formulated quantum mechanics as a wave equation — the Schrödinger equation — governing the evolution of quantum states. He reproduced hydrogen's energy levels from the equation and showed his wave mechanics was mathematically equivalent to Heisenberg's matrix mechanics. The Schrödinger equation remains the master equation of non-relativistic quantum mechanics, solved billions of times per day in chemistry and physics simulations worldwide.
1926 Quantum Era 🏆 Nobel Prize in Physics
Max Born
Zur Quantenmechanik der Stoßvorgänge On the Quantum Mechanics of Collision Processes Zeitschrift für Physik, 37, 863–867
Born proposed that Schrödinger's wave function doesn't describe a physical wave — its squared modulus gives the probability of finding a particle at a given location. This "Born rule" is the bridge between the wave function formalism and what we actually observe in experiments. It introduced fundamental, irreducible randomness into physics and sparked decades of debate about the meaning of quantum mechanics.
1928 Quantum Era 🏆 Nobel Prize in Physics
Paul A. M. Dirac
The Quantum Theory of the Electron Proceedings of the Royal Society A, 117, 610–624
Dirac combined special relativity with quantum mechanics to produce a relativistic wave equation for the electron. Spin emerged naturally from the mathematics without being inserted by hand. Most remarkably, the equation predicted the existence of a positive electron — the positron — before it was discovered. This was the birth of quantum field theory and the prediction of antimatter, one of the greatest theoretical triumphs in physics.
1935 Quantum Era
Albert Einstein, Boris Podolsky, Nathan Rosen
Can Quantum-Mechanical Description of Physical Reality Be Considered Complete? Physical Review, 47, 777–780
The EPR paper argued that quantum mechanics must be incomplete because two separated entangled particles seem to exhibit instantaneous correlations, which Einstein called "spooky action at a distance." Ironically, the paper spurred Bell's theorem (1964) and the subsequent experimental confirmation that quantum entanglement is real and non-local. The EPR correlations are now the engine of quantum cryptography and quantum computing.
1964 Modern Physics
John S. Bell
On the Einstein Podolsky Rosen Paradox Physics Physica, 1, 195–200
Bell proved that no "hidden variable" theory can reproduce all the predictions of quantum mechanics unless it allows faster-than-light influences. He derived a mathematical inequality — Bell's inequality — that any local realistic theory must satisfy. Quantum mechanics predicts violations of this inequality for entangled particles. Experiments by Clauser, Aspect, and others (culminating in Aspect's 1982 tests) confirmed the violations, ruling out local realism entirely. This is arguably the most profound experimental result in the history of physics.
1964 Modern Physics 🏆 Nobel Prize in Chemistry
Pierre Hohenberg, Walter Kohn
Inhomogeneous Electron Gas Physical Review, 136, B864–B871
Hohenberg and Kohn proved two theorems that founded density functional theory (DFT): the ground-state energy of any many-electron system is uniquely determined by its electron density, and the true density minimizes the total energy. This reduced the intractable N-body quantum problem to a functional of a single 3D function. DFT is now the dominant method in computational chemistry, materials science, and drug discovery, run billions of times daily worldwide.
1967 Modern Physics 🏆 Nobel Prize in Physics
Steven Weinberg
A Model of Leptons Physical Review Letters, 19, 1264–1266
In just three pages, Weinberg unified electromagnetism and the weak nuclear force into a single electroweak interaction, predicting the W and Z bosons and their masses. This is the cornerstone of the Standard Model of particle physics. The W and Z bosons were discovered at CERN in 1983 with exactly the predicted masses — one of the most dramatic confirmations in physics history.
2012 Modern Physics 🏆 Nobel Prize in Physics
CMS Collaboration, ATLAS Collaboration
Observation of a New Boson at a Mass of 125 GeV / Observation of a New Particle in the Search for the Standard Model Higgs Boson Physics Letters B, 716, 1–29 & 30–61
Announced on July 4, 2012, two independent experiments at the LHC — CMS and ATLAS — simultaneously reported the observation of a new boson consistent with the long-sought Higgs boson, the quantum of the field that gives elementary particles their mass. This was the final missing piece of the Standard Model, completing a theoretical framework built over fifty years. Peter Higgs and François Englert received the 2013 Nobel Prize.