Subcategories - Physics, Physicists
- Johannes Kepler
- Johannes Stark
- John Dalton
- John von Neumann
- Joseph Fourier
- Joseph Wilson Swan
- Joseph-Louis Gay-Lussac
- Joseph-Louis Lagrange
- Josiah Willard Gibbs
- Kamerlingh Onnes Liquefies Helium
- Kennelly and Heaviside Propose the Existence of the Ionosphere
- Kibble Proposes the Theory of Cosmic Strings
- Lamb and Retherford Discover the Lambshift
- Land Invents a Camera/Film System That Develops Instant Pictures
- Langevin Develops Active Sonar
- Langevin Develops Active Sonar for Submarine Detection and Fathometry
- Launching of the First Liquid-Fueled Rocket
- Lawrence Develops the Cyclotron
- Lemaître Proposes the Big Bang Theory
- Leonhard Euler
- Lev Davidovich Landau
- Libby Introduces the Carbon-14 Method of Dating Ancient Objects
- The Liquid Bubble Chamber Is Developed
- Lise Meitner
- Lord Kelvin
- Louis de Broglie
- Louis-Eugène-Félix Néel
- Ludwig Prandtl
- Luigi Galvani
- Lyons Constructs First Atomic Clock
- Manhattan Project
- Marconi Receives the First Transatlantic Telegraphic Radio Transmission
- Marrison Fabricates Electric Clock with Quartz Resonator
- Max Planck
- Michael Faraday
- Millikan Conducts His Oil-Drop Experiment
- Millikan Names Cosmic Rays and Investigates Their Absorption
- The Mössbauer Effect Is Used in the Detection of Gravitational Redshifting
- Müller and Bednorz Discover Superconductivity at High Temperatures
- Müller Develops the Field Ion Microscope
- Müller Invents Field Emission Microscope
- Müller Invents the Field Emission Microscope
- Nernst Develops Third Law of Thermodynamics
- Newton Formulates His Theory of Universal Gravitation
- Niels Bohr
- Nikola Tesla
- Nikolay Gennadiyevich Basov
- Noether Shows the Equivalence of Symmetry and Conservation
- Nuclear Magnetic Resonance Produces Brain Images
- Oppenheimer Calculates the Nature of Black Holes
