Rack // Ephemeris

Three Centuries of Discovery

195 events ImmersiveEquations
195 / 195
  1. 1665

    Huygenstwo pendulum clocks on one beam fall into step — synchrony, first noticed

  2. 1687

    Newtonuniversal gravitation — and the two-body ellipse, solved exactly

  3. 1733

    de Moivrethe first normal curve, as the limit of many coin flips

  4. 1747

    d'Alembertsolves the vibrating-string wave equation

  5. 1760

    Bernoullithe first mathematical epidemic model — weighing smallpox inoculation against the disease

  6. 1763

    Bayesbelief updates as posterior ∝ likelihood × prior — the rule the filter runs

  7. 1772

    Lagrangethe equilateral three-body solution and the L-points

  8. 1787

    Chladnibows a sand-strewn metal plate and the grains leap off the moving regions to settle on the still nodal lines — the first images of a vibration’s modes

  9. 1801

    Youngthe original two-slit experiment — light interferes, so light is a wave

  10. 1809

    Gaussleast squares to track Ceres from a few noisy sightings — estimation is born

  11. 1810

    Laplacethe Central Limit Theorem in its general form

  12. 1822

    Fourierclaims any periodic signal is a sum of sines (Théorie analytique de la chaleur)

  13. 1822

    Navierwrites the momentum equation — viscosity and all

  14. 1834

    Scott Russellobserves a solitary wave of translation on the Union Canal near Edinburgh — a heap of water that travels a mile without changing shape

  15. 1845

    Stokesputs it on rigorous footing: the modern Navier–Stokes form

  16. 1847

    Cauchymethod of steepest descent — follow the negative gradient downhill, the optimiser still in use

  17. 1848

    Wilbrahamfirst spots the overshoot at a jump — then it is forgotten for fifty years

  18. 1865

    Clausiusnames entropy and states the second law of thermodynamics

  19. 1867

    Maxwellproposes a tiny "demon" that sorts fast from slow molecules — apparently defeating the second law without doing work

  20. 1872

    Boltzmannthe H-theorem and S = k ln Ω — irreversibility from counting

  21. 1876

    Loschmidtthe reversibility objection: symmetric laws, an asymmetric world

  22. 1883

    Reynoldshis number, and the dye experiment that catches laminar flow breaking up

  23. 1887

    Michelson–Morleyfind no aether — light's speed refuses to add up

  24. 1890

    Poincaréno closed form for three bodies — the first sight of chaos

  25. 1890

    Poincarérecurrence: a closed system must eventually return near its start

  26. 1892

    Lyapunovhis stability theory gives the exponent λ that measures the stretch

  27. 1895

    Korteweg & de Vriesderive the KdV equation for shallow water waves and find its exact soliton solution, vindicating Scott Russell 60 years later

  28. 1899

    Gibbsexplains it: the ripple narrows but homes in on ≈8.95%, never vanishing

  29. 1900

    Bacheliermodels market prices as a random walk — finance meets diffusion, the first time-series

  30. 1905

    EinsteinBrownian motion ties the walk to atoms and Avogadro's number

  31. 1905

    Einsteinspecial relativity: c is invariant, and space and time mix

  32. 1906

    Markovthe Markov chain — a process whose next step depends only on the present, with a long-run equilibrium

  33. 1908

    Minkowskispacetime — the geometry in which the light cone is absolute

  34. 1908

    Langevinthe Langevin equation — Newton plus a random force; the stochastic differential equation that underlies every diffusion here

  35. 1909

    Haarthe first wavelet — a square step that splits a signal by scale

  36. 1911

    WeylWeyl’s law — the count of eigenfrequencies below a bound grows with the drum’s area, so the spectrum does betray the size, if not the shape

  37. 1912

    Perron & Frobeniusa positive matrix has one largest eigenvalue with an all-positive eigenvector — the unique, well-defined rank

  38. 1915

    Einsteingeneral relativity: matter curves spacetime, and light follows the curve

  39. 1915

    Whittakerthe interpolation formula that rebuilds a signal from its samples

  40. 1916

    Schwarzschildthe first exact solution — and with it, the event horizon

  41. 1918

    Julia & Fatouthe dynamics of z² + c — decades before anyone could see it

  42. 1919

    Eddingtonthe eclipse measures the bending at twice Newton's value — Einstein, famous overnight

  43. 1924

    Bosenew statistics for light quanta — particles that bunch together

  44. 1924

    de Brogliematter has a wavelength too — so particles can interfere

  45. 1925

    Einsteinextends Bose statistics to atoms and predicts the condensate

  46. 1925

    Isingsolves the 1D chain — and finds no phase transition (the model nearly dies here)

  47. 1925

    Lotkaderives the oscillating predator–prey equations in Elements of Physical Biology — a population read as a chemical-style dynamical system

  48. 1926

    Schrödingerthe wave equation — the whole future of ψ

  49. 1926

    Born|ψ|² is probability: the cloud itself (Nobel 1954)

  50. 1926

    Volterraexplains why the WWI pause in Adriatic fishing raised the shark fraction — the same equations, from his son-in-law fish-market data

  51. 1927

    Hundfirst spots tunnelling, in the splitting of molecular spectra

  52. 1927

    Madelungrewrites ψ as a fluid — a density and a flowing phase

  53. 1927

    Kermack & McKendrickthe SIR model and the epidemic threshold: an outbreak needs R₀ > 1 to take off

  54. 1928

    Gamowexplains alpha decay by tunnelling — radioactivity as a quantum leak

  55. 1928

    Nyquistfixes the rate: sample above twice the top frequency

  56. 1929

    Hubblegalaxies recede at a speed proportional to their distance — the universe is expanding

  57. 1929

    Szilárdresolves the demon with a one-molecule engine: one measurement yields kT ln 2 of work — and costs one bit of memory

  58. 1933

    Kotelnikovproves the sampling theorem in full

  59. 1933

    Zwickythe Coma cluster moves far too fast for its visible mass — most of the gravitating matter is unseen

  60. 1934

    Gausetests predator–prey in test tubes of Paramecium and Didinium — the predator eats all prey then starves; coexistence needs a refuge

  61. 1935

    Einstein, Podolsky & Rosenargue QM must be incomplete — "spooky action at a distance" can't be real

  62. 1936

    Whitneythe embedding theorem — any smooth d-manifold sits faithfully inside ℝ^(2d+1)

  63. 1937

    Landauthe general theory of phase transitions and the order parameter

  64. 1938

    Londonties superfluid helium to Bose–Einstein condensation

  65. 1944

    Onsagersolves the 2D Ising model exactly — T_c and the critical exponents, by hand

  66. 1944

    Gutenberg & Richterearthquake magnitudes follow a power law — no characteristic size, decades before anyone could say why

  67. 1944

    Itôstochastic calculus: the lemma that integrates dS exactly into a log-normal

  68. 1944

    von Neumann & MorgensternTheory of Games and Economic Behavior founds game theory — rational players, payoff matrices and the minimax theorem

  69. 1946

    Gabortiles time–frequency into "logons" and finds the joint-resolution limit

  70. 1948

    Shannon'A Mathematical Theory of Communication' — entropy, capacity, the whole field

  71. 1948

    von Neumann & Ulaminvent cellular automata — a self-reproducing machine on a grid

  72. 1949

    Onsagercirculation is quantised: vortices carry integer charge

  73. 1949

    Shannonmakes the sampling theorem a cornerstone of digital signal processing

  74. 1949

    Ulam · Metropolisthe Monte Carlo method — answer by sampling when the formula is hard

  75. 1949

    Hebb'neurons that fire together wire together' — memory as the strengthening of a connection

  76. 1950

    Hammingthe first error-correcting code — parity that names the flipped bit

  77. 1950

    Nashthe Nash equilibrium — every finite game has a stable strategy profile no player can beat by deviating alone

  78. 1951

    Belousovdiscovers a chemical reaction that oscillates in colour instead of settling to equilibrium — rejected as impossible by the journals, and ignored for a decade

  79. 1952

    Turing'The Chemical Basis of Morphogenesis' — diffusion can make pattern, not just smooth it

  80. 1953

    Metropolis, Rosenbluth & Tellerthe Metropolis algorithm — sample a Boltzmann distribution by accepting moves with probability min(1, e^−ΔE/T)

  81. 1957

    Esakithe tunnel diode puts the effect to work (Nobel 1973)

  82. 1957

    Broadbent & Hammersleyfounding paper on percolation — originally motivated by fluid flow through random media

  83. 1957

    Bellmandynamic programming and the principle of optimality — the value of a state is its best reward plus the discounted value of where you land; also names the curse of dimensionality

  84. 1958

    Rosenblattthe perceptron: a learning machine of weighted neurons — but a single layer cannot solve XOR

  85. 1959

    Hollingthe functional response — a predator saturates because prey take time to handle (type II); the realism that lets the model cycle and crash

  86. 1960

    Reed & Solomoncodes that armour CDs, QR codes and deep-space links

  87. 1960

    Kalmanthe recursive filter: optimal estimation of a linear system, one step at a time

  88. 1961

    Jönssonruns the double slit with single electrons, one at a time

  89. 1961

    Landauershows that erasing one bit of information dissipates at least kT ln 2 as heat — information is physical

  90. 1961

    FitzHugh & Nagumoreduce the Hodgkin–Huxley nerve impulse to two variables — a fast excitable voltage and a slow recovery — the minimal model of a firing, refractory medium

  91. 1963

    Lorenzthree equations for convection — the butterfly effect, chaos found by accident from a rounded printout

  92. 1963

    Rosenzweig & MacArthura graphical predator–prey model with logistic prey and saturating predation — isoclines that predict a stable point or a limit cycle

  93. 1964

    Sharkovskiiorders the periods: a map with a 3-cycle must have cycles of every length

  94. 1964

    Bellturns "is the world local?" into an inequality you can actually measure

  95. 1964

    Zhabotinskyrevives Belousov’s reaction and finds it makes travelling and rotating waves in a dish — chemistry that propagates like a nerve impulse or a heartbeat

  96. 1965

    Penrosecollapse to a singularity is inevitable — black holes are a robust prediction of relativity, not a fluke (Nobel 2020)

  97. 1965

    Cooley & Tukeythe FFT makes the transform cheap — now inside MP3, JPEG, every analyser

  98. 1960s

    Kirkpatrick et al.Monte Carlo computation of p_c for the square lattice ≈ 0.5927

  99. 1965

    Samuelsongeometric (not arithmetic) Brownian motion for prices — they can never go negative

  100. 1965

    Zabusky & Kruskalrediscover solitons on a computer, observe that two pulses pass through each other unchanged — and coin the name "soliton"

  101. 1966

    Kac“Can one hear the shape of a drum?” — asks whether two differently-shaped membranes could ever share an identical spectrum of tones

  102. 1967

    Winfreebiological oscillators sync once the coupling beats the spread

  103. 1967

    Mandelbrot'How Long Is the Coast of Britain?' — fractional dimension enters science: the length depends on the ruler

  104. 1967

    Viterbithe Viterbi algorithm — dynamic programming recovers the single most-likely hidden path through a noisy sequence, exactly, in one backward sweep

  105. 1968

    Venezianohis amplitude for the strong force secretly describes a string

  106. 1969

    Clauser, Horne, Shimony & Holtthe experimentally testable form of Bell's bound, S ≤ 2

  107. 1969

    Apollothe Kalman filter flies the guidance computer to the Moon and back

  108. 1970

    Nambu, Nielsen & Susskindread it literally: the constituents are vibrating strings

  109. 1970

    Conwaythe Game of Life makes cellular automata famous

  110. 1970

    Gosperfinds the glider gun — Life grows without bound, so it can store and move information

  111. 1970

    Zel'dovichthe approximation that lets gravity be run by hand — matter collapses first into sheets (pancakes), then filaments, then knots

  112. 1970

    Baum, Petrie, Soules & Weissthe hidden Markov model with forward–backward and Baum–Welch — infer the hidden states, and the chain itself, from the observations alone

  113. 1971

    Wilsonthe renormalisation group explains universality (Nobel 1982)

  114. 1971

    Hafele–Keatingflying atomic clocks confirm time dilation directly

  115. 1971

    Rosenzweigthe paradox of enrichment — raising the prey carrying capacity destabilises the equilibrium into ever-wider cycles that can drive extinction

  116. 1972

    Gierer & Meinhardtname the design rule: short-range activation, long-range inhibition

  117. 1972

    Mayasks whether a large complex system is stable and finds it usually is not — richly connected ecosystems tend to be less stable, not more

  118. 1972

    Winfreeshows the rotating chemical spiral turns about a phase singularity — a point where phase is undefined — and ties the same geometry to cardiac fibrillation

  119. 1973

    Black · Scholes · Mertonthe same log-normal, priced: option value as a discounted forecast

  120. 1973

    Maynard Smith & Pricethe evolutionarily stable strategy — game theory carried into biology, where fitness rather than reason selects the move

  121. 1974

    Littlecasts a neural network as a spin system — persistent firing states are the stored memories

  122. 1975

    Li & Yorkecoin the word — “Period Three Implies Chaos”

  123. 1975

    Kuramotothe exactly solvable synchronization model — order parameter r and the critical K_c

  124. 1976

    Robert Maythe logistic map as a toy ecology (Nature) — a simple law, an uncomputable fate

  125. 1978

    Feigenbaumfinds the doubling ratio δ ≈ 4.6692 is universal — on a pocket calculator

  126. 1979

    Kaplan–Yorkeconjecture links the Lyapunov exponents to the attractor's fractal dimension

  127. 1980

    Benettinan algorithm to measure λ from a shadow orbit — the method the rack uses live

  128. 1980

    Tsirelsonproves quantum mechanics can violate CHSH only up to 2√2

  129. 1980

    Mandelbrotcomputes the set at IBM and reveals the shape

  130. 1980

    Peeblesthe gravitational theory of how faint early-universe ripples grow into the cosmic web (Nobel 2019)

  131. 1980

    Packard, Crutchfield, Farmer & Shaw“Geometry from a Time Series” — reconstruct an attractor from a single signal’s own delayed copies

  132. 1981

    Binnig & Rohrerthe scanning tunnelling microscope feels single atoms (Nobel 1986)

  133. 1981

    Witten & Sanderdiffusion-limited aggregation — random walkers stick on contact into a branching fractal of dimension ≈ 1.71

  134. 1981

    Takensproves it: delay-coordinate embedding is generically diffeomorphic to the true attractor — same invariants

  135. 1981

    Axelrod & Hamiltonthe iterated tournament — Tit-for-Tat beats every cleverer rule; cooperation evolves among selfish agents that meet again

  136. 1981

    Benzi, Sutera & Vulpianiintroduce stochastic resonance to explain the 100,000-year ice-age cycle: orbital forcing alone is too weak — noise from climate fluctuations makes it detectable

  137. 1982

    Sparrowthe definitive study of the Lorenz equations

  138. 1982

    Aspectswitches the analysers in flight — closes the locality loophole, S ≈ 2.7

  139. 1982

    Nienhuisexact critical exponents β = 5/36, ν = 4/3 via Coulomb gas / conformal field theory

  140. 1982

    Hopfielda recurrent net whose energy only falls, so memories are the basins of attraction it rolls into

  141. 1982

    Berlekamp, Conway & Guy'Winning Ways' proves Life is Turing-complete — a universal computer built from one rule

  142. 1982

    Douady & Hubbardprove M is connected, and give it his name

  143. 1982

    Bennettproves the demon cannot violate the second law: the erasure of its memory ledger, not the measurement, is the thermodynamic cost

  144. 1982

    Andersonthe reverse-time SDE — a diffusion run backward is itself a diffusion, driven by the score of the density; the theorem generative models would later stand on

  145. 1983

    Gray & Scottthe autocatalytic reaction–diffusion model this engine runs

  146. 1983

    Wolframsorts the 256 elementary rules into four behaviours

  147. 1983

    Grassberger & Procacciathe correlation dimension — read a strange attractor’s fractal dimension straight off the reconstructed cloud

  148. 1983

    Kirkpatrick, Gelatt & VecchiOptimization by Simulated Annealing — melt a hard problem, then cool it slowly through Metropolis moves into its best state

  149. 1984

    Morlet & Grossmannformalise the continuous wavelet transform, out of seismic traces

  150. 1984

    Brady & Ballcopper electrodeposits grow as DLA fractals — the model caught in the lab, the same dimension measured in metal

  151. 1985

    Amit, Gutfreund & Sompolinskythe spin-glass calculation: the net stores ≈0.138N patterns before the basins dissolve

  152. 1985

    Černýindependently applies thermodynamic annealing to the travelling-salesman problem — the method arrives twice at once

  153. 1986

    Rumelhart, Hinton & Williamsbackpropagation trains hidden layers efficiently — the multilayer network finally learns

  154. 1986

    ReynoldsBoids: three local rules — align, cohere, separate

  155. 1987

    Bak, Tang & Wiesenfeldself-organized criticality: a sandpile tunes itself to the critical point and emits 1/f noise — no parameter set by hand

  156. 1988

    Daubechiescompactly-supported orthonormal wavelets — the basis inside JPEG 2000

  157. 1988

    Suttontemporal-difference learning — update a prediction from a later, better prediction, with no model of the world; the bracket that becomes Q-learning

  158. 1989

    Laskarthe inner Solar System is chaotic, with a ~5-million-year horizon

  159. 1989

    Mallatmultiresolution analysis + the fast wavelet transform

  160. 1989

    Hart, Sandin & Kauffmandistance-estimated ray tracing — march a ray by a safe lower bound on the distance to the surface, which is what makes a 3D escape-time fractal renderable at all

  161. 1989

    WatkinsQ-learning — a model-free, off-policy rule that provably converges to the optimal action-values just by trying, watching and updating

  162. 1989

    Hamiltonthe Markov-switching model carries hidden-state inference into economics — reading booms and recessions as latent regimes behind the noise of GDP and returns

  163. 1990

    De Kepperfirst chemical Turing patterns seen in the lab (the CIMA reaction)

  164. 1990

    Dharthe abelian sandpile: topplings commute, the recurrent states form a group, and the identity is a fractal

  165. 1991

    Shishikuraproves the Mandelbrot boundary has Hausdorff dimension 2

  166. 1992

    Nowak & Mayspatial games — cooperators and defectors on a grid form ever-shifting fractal patterns; structure alone sustains cooperation

  167. 1992

    TesauroTD-Gammon reaches near-expert backgammon by playing millions of games against itself — temporal-difference learning, scaled up, beats hand-tuned programs

  168. 1992

    Gordon, Webb & Wolpertanswers Kac — no: they build two different polygonal drums with exactly the same spectrum. You can hear the area and perimeter, but not the shape

  169. 1993

    Berrouturbo codes reach within a whisker of the Shannon limit

  170. 1994

    Watts & Strogatz · Barabásipercolation transitions in real-world networks: internet, epidemics, markets

  171. 1994

    Moss, Pierson & O'Gormandemonstrate stochastic resonance in biological neurons — sensory systems appear to operate near the optimal noise level for signal detection

  172. 1995

    Englert–Greenberger–Yasinpin down the exact duality relation V² + D² ≤ 1

  173. 1995

    Cornell, Wieman & Ketterlethe first gaseous BEC, at JILA and MIT (Nobel 2001)

  174. 1995

    Vicsekthe minimal model — collective motion as a true phase transition

  175. 1998

    Watts & Strogatzsmall-world networks — a few long-range links collapse the distance a contagion must travel

  176. 1998

    Page & BrinPageRank — rank the web by its link structure alone; a random surfer’s equilibrium, and the founding of Google

  177. 1998

    Gammaitoni, Hänggi, Jung & Marchesonipublish the landmark review of stochastic resonance, establishing it as a universal phenomenon in nonlinear noisy systems

  178. 1999

    Jos Stam“Stable Fluids” — an unconditionally stable solver; real-time fluids in a browser

  179. 2001

    Pastor-Satorras & Vespignanion scale-free networks the epidemic threshold can vanish — hubs change everything

  180. 2002

    Couzinmaps the switch between swarm, torus and aligned flock

  181. 2004

    Cookproves Rule 110 is Turing-complete — a universal computer

  182. 2005

    Strogatzthe Millennium Bridge wobble: pedestrians lock step with the sway

  183. 2008

    Ballerinireal murmurations: each bird tracks ~7 neighbours, by rank not distance

  184. 2009

    White & Nylanderthe Mandelbulb — take the nth power of a point in spherical coordinates and z → zⁿ + c becomes a 3D fractal with genuine surface detail

  185. 2012

    Krizhevsky, Sutskever & HintonAlexNet: the same gradient descent, scaled to GPUs, wins ImageNet and ignites deep learning

  186. 2012

    Sugihara et al.convergent cross mapping — “shadow manifolds” turn reconstruction into a test for causation between time series

  187. 2015

    DeepMindthe Deep Q-Network learns to play 49 Atari games from raw pixels and the score alone, at human level — Q-learning with a deep net as the value function

  188. 2015

    Sohl-Dickstein et al.deep unsupervised learning by nonequilibrium thermodynamics — destroy data with a slow diffusion, then train a network to reverse each step

  189. 2016

    DeepMindAlphaGo defeats Lee Sedol at Go — self-play reinforcement learning plus tree search solves a game long thought a decade away

  190. 2019

    Event Horizon Telescopephotographs a black hole's shadow for the first time

  191. 2019

    Song & Ermonscore-based generative modelling — learn the gradient of the log-density and sample by following it with Langevin dynamics

  192. 2020

    Ho, Jain & Abbeeldenoising diffusion probabilistic models — the clean recipe that made diffusion the engine behind modern image generators

  193. 2021

    Song et al.unifies diffusion as a reverse-time SDE with a deterministic probability-flow ODE twin — one framework for every sampler

  194. 2022

    Aspect, Clauser & Zeilingerthe Nobel for the experiments proving the world is not locally real

  195. 2024

    Hopfield & Hintonthe Nobel Prize in Physics for the physics of memory and learning in neural networks

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