T = 0 (13.7 BYA)
“the big bang”
The planck epoch
Maybe a singularity, maybe not
maybe a period of cosmic inflation prior to regular expansion. This part is all hypothetical based on how we balance out current equations
if universe started as singularity, a period of special cosmic inflation is hypothesized as necessary order to explain the uniformity of the visible universe
All fundamental forces unified as one
We can’t really understand this moment until we have a working theory of quantum gravity
T = 10^-43 seconds
The grand unification epoch
Gravity separated from the other forces
T = 10^-36 seconds
The electroweak epoch
Strong nuclear force separates from other fundamental forces
T = 10^-34 seconds
End of special cosmic inflation, if it happened. beginning of regular espansion / what we can explain with current theories, though we haven’t reached what’s reproducible in a particle accelerator yet
~T = 10^-32 seconds
Universe reached temperatures required for the production of a quark-gluon plasma, as well as other elementary particles.
Particle-antiparticle pairs continuously produced and destroyed
At some point, an unknown process violates the conservation of baryon number, leading to a small excess of quarks and leptons over antiquarks and antileptons, resulting in predominance of matter over antimatter
T = 10^-12 seconds
Electromagnetic and weak nuclear force separate, all fundamental forces and parameters of elementary particles are in their present form
Fundamental particles / forces:
Gravity
Standard Model Fields
Fermions (= antimatter forms)
Quarks
up
down
strange
charm
top
bottom
Leptons
electrons
muon
tau
electron neutrinos
muon neutrinos
tau neutrinos
Gauge Bosons
Photons / Electromagnetic force
Gluon / Strong nuclear force
Z + W / Weak nuclear force / beta decay / radioactivity
Scalar Boson: Higgs / mass giving
T = 10^-6 seconds
(less speculative from this point forward, since particle energies drop to levels reproducible in particle accelerators)
quarks and gluons combine into baryons:
uud quark combos into protons
ddu quark combos into neutrons
mass annihilation of most particles and all antiparticles
T = 1 second
mass annihilation of most electrons and all positrons
after annihilations, protons, neutrons, and electrons no longer moving relativistically - energy density of the universe is now mostly photons
T = a few minutes
neutrons combine with protons to form deuterium and helium nuclei, in addition to uncombined protons (hydrogen nuclei). Possibly a bit of lithium nuclei
elements are defined by the number of protons in a nucleus
still too hot for the electromagnetic force to bind electrons to nuclei, early universe remains a hot, opaque plasma
The milky way begins as one or several small overdensities in the universe
T = ~ 378,000 YEARS
“recombination”
universe is cool enough for the electromagnetic force to bind electrons to nuclei to create electrically-neutral atoms, photons are able to free stream, universe becomes transparent (cosmic microwave background / relic radiation).
an element gains a neutral electric charge when the number of protons = number of electrons
Note: orange glow would fade at the rate of combination; event though CMB was less red-shifted at the time, it would still already by outside of the visible spectrum, so no persistent glow coming from the final photon release
Gas forms into galaxies under the gravity of dark matter
Gas inside of galaxies collapses into solar systems
Early stars die, creating and spreading heavier elements
~11 BILLION YEARS AGO
The milky way merges with another large galaxy, known as the kraken
~4.6 BILLION YEARS AGO
a cloud of gas in the milky way collapses to form the sun, remaining dust starts to clump together
~4.5 BILLION YEARS AGO
earth pretty much formed
another mars-sized planet crashes into earth, forming the moon
the hadean epoch lasts ~.5 billion years
constant bombardment
Earliest water + many, if not all building blocks of life brought to earth by comets, meteorites, etc
origin of natural selection. one theory - different combinations of rna connect and break apart - initially selecting for stronger, more stable bonds, and longer chains. longer chains increase probability of an autocatalytic set emerging stochastically
a population of autocatalytic rna enzymes was shown to ultimately yield and then be dominated by recombinant replicators
beneficial cooperation between rna chains may have paved the way for the protocell (like a multicellular development, one layer down)
single-celled life
LUCA
molecule = combinations of atoms
molecules important to life:
proteins / amino acids
ribose / ribonucleic acide (RNA)
deoxyribose / deoxyribonucleic acid (DNA)
lipids
~4 BILLION YEARS AGO
Late heavy bombardment
~4 BILLION YEARS AGO - ~2.5 BILLION YEARS AGO
The archean epoch
Photosynthesis
Earliest oxygen
~2.5 BILLION YEARS AGO - ~500 MILLION YEARS AGO
The proterozoic epoch
Eukaryotes
cell nucleus
mitochondria
Sexual reproduction (assuming that didn’t emerge in rna world)
Multicellular life
Fungi
Plants
Animals
~500 MILLION YEARS AGO
The cambrian explosion, the cambrian period begins
Chordates
Vertebrates
~485 MYA - ~443 MYA
The ordovician period
~443 MYA - ~419 MYA
The silurian period
~419 MYA - ~358 MYA
The devonian period
~358 MYA - ~298 MYA
The carboniferous period
Amphibians appear - spending part of their time on land
Amniotes appear - adapted for terrestrial living
Synapsids appear
~320 MYA
Pangea forms
~298 MYA - ~251 MYA
The permian period
~251 MYA - ~201 MYA
The triassic period
Mammals appear
~201 MYA - ~145 MYA
The jurassic period
~145 MYA - ~66 MYA
The Cretaceous period
~66 MYA
The K-Pg mass extinction
~66 MYA - ~23 MYA
The Paleogene period
Primates appear
~23 MYA - ~2.5 MYA
The Neogene period
Hominids (the great apes) appear
~4.5 MYA
Australopithecus appear and split off from other great apes
Beginning of use of stone tools?
~2.8 MYA
Genus Homo splits off from Australopithecus
~2.5 MYA - ~12,000 YEARS AGO (~10,000 BCE)
The Ice Age
~300,000 YEARS AGO
Anatomically modern humans (homo sapiens) emerge in africa, splitting off from other archaic humans
Dispersal throughout Africa begins
~70,000 YEARS AGO
Arrival in arabian peninsula
~65,000 YEARS AGO
Arrival in south asia, begin dispersing along the coast and throughout oceania
~50,000 YEARS AGO
Arrival in the fertile crescent
Begin dispersing through Europe and the rest of Asia
~35,000 YEARS AGO
Arrival in Japan
~25,000 YEARS AGO
Humans arrive in the Americas and begin dispersing throughout
~15,000 BCE
Earliest evidence of humans in the Andean region
Earliest evidence of domestication of dogs
~12,000 YEARS AGO (~10,000 BCE)
The agricultural revolution (end of ice age?)
Beginnings of civilizations
Mesopotamian civilization emerges
~9000 BCE
Domestication of sheep, goats, pigs, cows
~7000 BCE
Agricultural beginnings of the mesoamerican cultures
~5000 BCE
Yangshao culture emerges
Domestication of chickens
~3,500 BCE
Caral-Supe civilization - first complex society of the Andean civilizations - emerges
Domestication of horses in asia
~3,300 BCE
Indus Valley civilization emerges
~3,100 BCE
Earliest known recorded history
Ancient egyptian civilization coalesces
Sumerians, Babylonians, ancient Nubians study angle measure, ratios, triangles, and divisions of circles
Domestication of other animals
~3,000 BCE
Although a sense of arithmetic is probably prehistoric, it’s around now that more complex and structured approaches start to appear, probably spurred on by the needs of larger more complex civilization
Longshan culture emerges
~2,000 BCE
Bronze age
Earliest recorded beginnings of geometry
~1,200 BCE
Iron age
Olmecs - first major mesoamerican civilization - emerges
~539 BCE
Fall of Babylon
~460 - ~370 BCE
Hippocrates applies idea of humors (chemical systems regulating human behavior) to medicine, suggesting they are the vital bodily fluids of blood, phlegm, yellow bile, and black bile
~450 BCE
Empedocles proposes four classical elements: earth, water, air, and fire
~424 - 348 BCE
Plato articulates an emission theory of vision, suggesting that the eyes project rays of light, illuminating things in front of them, until something blocked the eye-rays, which would be perceived as darkness
300s BCE
Eudoxus’ and Callippus’ theories of concentric spheres
Aristotle:
Theory of concentric spheres, building off of previous work by Eudoxus and Callippus. While Eudoxus and Callippus may not have believe their models to be the true nature of the universe (rather just a calculation tool), Aristotle did
Describes two kinds of mechanics “violent motion” and “natural motion”. Rather than being based on momentum and equilibrium, an object’s natural state is to be at rest.
Theory of vision involving the separation of “form” from “matter”
Theorizes that the hazy light of the milky way in the sky was caused by an atmospheric phenomenon
~350 BCE
Aristotle adds fifth element, aether, to explain the different behavior of the heavens
140 BCE
Hipparchus proved theorems equivalent to modern trigonometry, but expressed geometrically
27 BCE
Start of the roman empire
100s CE
Ptolemy’s uses epicycles to explain the motion of planets in an earth-centric universe - geocentrism is standardized
476 CE
Fall of the western roman empire
Medieval period in europe
Medieval art very much about religion and the metaphysical, but also perhaps a rejection of rome’s self-perceived superiority, and with it its focus on rationalism
~786 - ~1258 CE
The Islamic Golden age - period of scientific, economic, and cultural flourishing
Formalization of alchemy and chemistry - including some of the earliest classifications of chemical substances
Al-Battani accurately determine’s the length of a solar year
Nasir al-Din al-Tusi wrote a revision of ptolemy’s celestial model, and developed trigonometry
Abu Bakr al-Razi identifies smallpox and measles, and recognizes fever as part of the body’s defenses, and questioned the greek idea of the four humors
al-Zahrawi pioneers surgical tools, supplies, and procedures
Study of optics - Development and improvement of lenses for magnification and improvement of vision
Ibn al-Haytham - rejected aristotelian notion and euclid/ptolemaic notions of vision, postulating that vision occurs by way of light waves forming a cone - argued that the mathematics of reflection and refraction needed to be consistent with anatomy of the eye, and was an early proponent of the scientific method
Ibn Sina builds on john philoponus’ rejection of the aristotelian view of motion, adopting idea that moving object has force which is dissipated by external agents like air resistance
825 CE
Al-Jabr is published, formalizing algebraic methods that had been around for a while but mainly used to solve specific / geometric problems, not abstract ones.
950 - 1250 CE
Medieval warm period
1300 - 1850 CE
Little ice age
1315 - 1317 CE
Great famine
1347 - 1351 CE
Black death
Along with the great famine and other political and social upheavals and revolts of the time, the “crisis of the late middle ages” is seen as the beginning of the renaissance era
Associated with desire to revive and surpass the ideas and achievements of classical antiquity
1438 CE
The Inca Empire is formed
1440s CE
Invention of the printing press by Johannes Gutenberg
Would eventually help usher in the scientific revolution, decisively changing the way scientific thought was both recorded and disseminated
~1450 CE
Formation of the Iroquois League - North America’s first democracy
1453 CE
Fall of the eastern (byzantine) roman empire to the ottoman turks
1492 CE
Columbus arrives in the bahamas
1490 - 1527 CE
High renaissance
Focus on the human realm. Focus on realism, attention to detail, precise study of human anatomy
~1502 CE
Amerigo Vespucci publishes Mundus Novus proving Columbus had reached a new continent, not an eastern part of asia
1510 - 1520 CE
Development of mannerism - which involved expressively exaggerating features - emerges out of an anxiety amongst younger artists - a crisis that everything there is to discover has already been discovered
1517 CE
Protestant reformation begins
1527 CE
Henry VIII’s dispute with the Pope begins, leading to the English reformation
1543 CE
Copernicus formulates a helio-centric model of the universe, beginning of the “scientific revolution”
1572 CE
The Inca Empire falls to Spain
1607 CE
First permanent british settlement in america
1600 - 1750 CE
Baroque movement - exuberant detail, grandeur
Encouraged by the catholic church as a means to counter the austerity and simplicity of protestant art, architecture, and music
Rococo emerges towards the end as an even more flamboyant, natural conclusion - featuring more and more asymmetries
1609 CE
Johannes Kepler publishes evidence that, among other things, planets move in elliptical orbits
1610 CE
Galileo publishes his observations confirming, among other things, Copernicus’ helio-centric model
Also proving that the milky way consists of many stars
1620 CE
Francis Bacon’s Novum Organum is published, helping to spread the philosophy of the scientific method
1644 CE
Descartes’ book states that bodies can only act on each other. Although it required a universal medium - the aether - to work, the idea was vindicated through particle physics and interactions via bosons
1661 CE
Publication of the skeptical chemist, first publication to distinguish between chemistry and alchemy
1665 CE
Calculus is formalized independently by Isaac Newton and Gottfried Wilhelm Leibniz, though elements of it had appeared in ancient egypt, greece, china, the middle east, medieval europe and india.
1669 CE
law of superposition proposes that in undeformed strata sequences, layers are older the further down you go
1672 CE
Isaac Newton publishes results of splitting light through a prism, revealing nature of white light as a combination of the full visible spectrum, and inventing spectroscopy
1687 CE
The publication of Isaac Newton’s Principia, expounding his lows of motion and universal gravitation
1750 CE
ability to produce phosphorous in bulk (originally discovered through attempts to turn urine to gold via alchemy)
1752 CE
Benjamin Franklin’s kite experiment
1755 CE
Immanuel Kant correctly speculates that the milky way might be a rotating body of a huge number of stars held together by gravitation forces akin to the solar system but on a much larger scale
1760 CE
Beginnings of the industrial revolution
beginning of the anthropocene
1766 CE
Cavendish is first to isolate hydrogen in a lab, and recognize it as a distinct element
Also first to combine hydrogen and oxygen to form water
1750 - 1850 CE
Neoclassicism - ancient ruins found at athens and naples reignited a passion for the past - focus on symmetry and order, overlapping with age of enlightenment
1771 CE
Jérôme Lalande, using data collected from global, international expeditions to observe the transit of venus in 1761 and 1769, calculates the distance between the earth and the sun to within 2.3% of error
1775 CE
initial results from the schiehallion experiment prove newton’s inverse square law of gravity
1776 CE
Final results from schiehallion experiment calculates earth’s mass as 4,500 kg·m−3, less than 20% away from the modern value. From this, was also able to correctly surmise the earth contained a dense, metallic core, and make first calculations of the mass of other celestial bodies
George Palmer proposes a theory of visible light perception involving three photoreceptor cells, but incorrectly postulates that light itself is made up of three distinct types, as opposed to a spectrum
American independence from Britain
1780 - 1850 CE
Romanticism - reject the order, harmony, and logic of neoclassicism
Kind of a rebellion against scientific reason in favor of subjectivity and primacy of the individual
1781 CE
William Herschel discovers Uranus and becomes court astronomer. uses his new resources to produce the first systematic map of the milky way, which comes out amoeba-shaped since he only uses number of stars in a region to estimate size, not understanding that brightness is related to distance
1789 - 1794 CE
Antoine Lavoisier contributes majorly to the chemical revolution - reforming chemistry, resulting in the law of conservation of mass, and oxygen theory of combustion
1795 CE
Hutton publishes his principles of geological change through erosion and upheaval
hutton also proposes theory of uniformitarianism - idea that the earth is shaped continuously and gradually, in opposition to catastrophism - idea that earth is shaped by sudden biblical disasters
1796 CE
cuvier is first to describe mastodon, and also puts forth a formal theory of extinctions
william smith realizes fossils could be used to correlate ages of rocks to other sites, and makes map of britain’s strata
1797 - 1798 CE
Cavendish experiment - first experiment to accurately measure gravitational force in a lab, first to yield accurate values for the gravitational constant and get an accurate mass of the earth
1800s CE
Lyle champions geological theory of unitarianism, but with the oversights of not buying into any sudden shifts like ice ages or extinctions - aside for these setbacks, his writings shaped and influenced modern geology
American expansion
1802 CE
Thomas Young postulates existence of three types of photoreceptors with different but overlapping sensitivities
1804 CE
Lewis and clark expedition sets out, in part hoping to disprove theories of evolution and extinctions by finding living mastodons
1800 CE
Huge boom in discovered dino fossils across america and europe
1812 CE - 1847 CE
Mary Anning finds ichthyosaurus fossil at lime regis, and subsequently others - inc first plesiosaurs, and one of the first pterosaurs
1818 CE
Ocean liners offering regular comfortable passenger service begin operation
Mary Shelley publishes Frankinstein, inspired by contemporary notion of élan vital - a vital force which causes unalive things to become alive, and which could potentially be triggered with electricity
1827 CE
Robert Brown observes brownian motion
1828 CE
Synthetic ultramarine is invented
1840s CE
Electrical telegraph comes into use
Observations by william parsons reveal spiral structure of distant galaxies (then called nebulae)
1848 - 1900 CE
Realism - spurred on by rise of journalism, invention of photography, plus anti-romantic movement - interest in accurately capturing reality
1850 CE
Herman von Helmholtz develops theory of color vision further, describing photoreceptor cells as preferring short, medium, and long wavelengths
1856 CE
First direct evidence for the existence of three color receptor cells
1859 CE
On the origin of species - foundation of evolutionary biology
darwin also calculates the geological processes required to form part of southern england to have taken 306,662,400 years - way older than current accepted wisdom about the age of the earth
1864 CE
James Clerk Maxwell proposes a comprehensive theory of electromagnetism - predicted couple electric and magnetic fields could travel through space as an electromagnetic wave, and that light consists of electromagnetic waves in certain wavelengths
1865 CE
Gregor Mendel’s laws of inheritance - reports that traits are inherited in a predictable manner through independent assortment and segregations (later known as genes)
1865 - 1885 CE
Impressionism - emphasis of one’s perception over nature
roughly the start of movements considered “modern art”
1885 - 1910 CE
Post-impressionism - subjective visions and symbolic meaning over observations of the outside world
1869 CE
Mendeleev publishes the periodic table of the elements
1878 CE
First hydroelectric dam
1878 - 1886 CE
Muybridge’s photographic studies of motion
1879 CE
Electric lightbulb patented
1882 CE
First coal-fired power station
1885 CE
First commercially-viable automobile
1886 CE
Westinghouse develops AC system, which could reach a larger area more efficiently
Heinrich Hertz experimental proves the existence of electromagnetic waves
1888 CE
First electric streetcar
1890 CE
First electric subway
1890 - 1910 CE
Art Nouveau
1894 CE
Birth of the kinetoscope
Birth of the radio transmitter / receiver
1895 CE
Simon Newcomb uses data from 1874 and 1882 transits of venus to refine the AU down to within 0.06% error
Discovery of X-rays by Wilhelm Röntgen
1896 CE
Radioactivity discovered by Marie Curie and Henri Becquerel
1900 - 1935 CE
Fauvism - bold, intense colors decoupled from their descriptive, representational purpose - an intermediary between post-impressionism and cubism and expressionism
1905 CE
Einstein’s four papers
Photons
Special relativity - speed of light is immutable, constant, independent of observer’s motion
Equivalence between mass and energy - E=mc^2
One of Einstein’s papers presents brownian motion as a way to indirectly confirm the existence of atoms and molecules
1905 - 1920 CE
expressionism
response to conflicting worldviews and loss of spirituality, distortion of form and color to express raw emotion
1907 CE
Beginning of commercially viable color photography
1908 CE
thanks to invention of photography and spectroscopy, henrietta leavitt discovers ability to use cepheid variables as standard candles
1907 - 1914 CE
Cubism
1914 CE
Film industries established
1914 - 1918 CE
WW1
1915 CE
Einstein publishes his theory of general relativity, describing the observed effects of gravity as the warping of spacetime
1916 - 1950 CE
Surrealism - rejection of rationality as cause of ww1 and suppressing of imaginative thoughts. Influenced by karl marx and sigmund freud
1920 CE
Beginnings of commercial broadcast radio with Frank Conrad + Westinghouse setting up KDKA
Proposal that stars get their energy from nuclear fusion
1920s CE
Edwin Hubble conclusively confirms the existence of other galaxies outside of our own
Paul Dirac’s attempts to quantize the electromagnetic field result in QED - Quantum Electrodynamics, which will be further refined by others over subsequent decades, and creates the foundation of the standard model
1920s and 1930s CE
Modern synthesis - connected natural selection and popular genetics into a unified theory that included random genetic drift, mutation, and gene flow
1923 CE
16mm film introduced as a cheap alternative for amateurs
1930s CE
Neutrino postulated by Wolfgang Pauli
Cinema has become the principal form of popular entertainment
Introduction of the vinyl record
Fritz Zwicky postulates neutron stars and supernovae
Zwicky postulates about there not being enough matter to explain motion of galaxies, hence the need for dark matter
1931 CE
Big bang theory proposed by Lemaître
1932 CE
8mm film released as a cheap alternative to 16mm for home movies
1935 CE
Kodachrome goes on sale - first commercially successful integral tripack system - that is, first commercially successful color film that didn’t require a special camera for the creation of color separated negatives
AC biasing technique discovered, allowing for high-quality audio recording to magnetic tape
1938 CE
Discovery of nuclear fission
1939 - 1945 CE
WWII
1942 CE
First man-made nuclear reactor
1945 CE
World’s first nuclear explosion
1946 CE
Point at which the majority of american homes have a telephone
Proposal that stars form elements up to iron during their normal life cycle
1947 CE
Start of the cold war
Pre-recorded broadcasts via magnetic tape introduced to broadcast radio industry
1940s and 1950s CE
Discovery of hadrons
1950s CE
Television replaces radio as the dominant broadcast medium
1950s and 1960s CE
Pop art
1951 CE
Gerard Kuiper conjectures the existence of the kuiper belt
1953 CE
Building on the work of others, Watson and Crick propose the double-helix structure of DNA
1954 CE
Paper showing that elements heavier than iron created in supernovae - also solving one of the main problems with the big bang theory
1956 CE
Experimental detection of the neutrino (resulting from nuclear reactor)
1957 CE
Flights have surpassed ocean liners as the preferred means of crossing the atlantic
1961 CE
Sheldon Glashow combines electromagnetic interactions and weak interactions into standard model
1965 CE
First neutrino found in nature detected
Age of the universe estimated to be within 10-25 Billion years, but estimation of the hubble constant meant the value remained uncertain
Super-8 film released as a better-quality and easier-to-use film for home movies, designed to accommodate sound as well
1960s CE
Solar neutrino problem - homestake experiment detects only 1/3 of the neutrinos coming from the sun as expected. This conflicted with expectations because neutrinos were believed to be massless, and therefore wouldn’t change from the single kind produced by the sun, when in fact they have mass, and therefore do experience time and oscillate
Direct radar measurements of the distance to mercury and venus become available
1964 CE
Discovery of the CMB, providing observational evidence of one of the big bang theory’s predictions
1967 CE
Steven Weinberg and Abdus Salam incorporate Higgs mechanism into the standard model
1968 - 1972 CE
Manned apollo missions
1970s CE
Postmodernism - skepticism, irony, and philosophical critiques
Rejection of modernism / modern art movements
Breh
1973 CE
Neutral weak currents caused by Z bosons discovered experimentally at CERN
Theory of Quantum Chromodynamics - i.e. the strong interaction - is formed and experiments confirm that hadrons are composed of fractionally charged quarks
1974 CE
Stephen Hawking predicts Hawking radiation
1980 CE
Vera Rubin and collaborators present strong observational evidence for the presence of and amount of dark matter in galaxies
1983 CE
W± and Z0 bosons discovered experimentally at CERN
1983 CE
Birth of the internet / TCP/IP
1989 CE
Birth of the world wide web
Invention of the blue LED (completing the RGB set)
1991 CE
End of the cold war
1992 CE
Discovery of kuiper belt objects other than pluto and charon lead to confirmation of the kuiper belt’s existence (and pluto’s reclassification)
1998 CE
Experiments begin to show that solar and atmospheric neutrinos can change flavor, resolving the solar neutrino problem and accounting for the originally measured deficit
First direct evidence of dark energy from supernova observations
1999 CE
NoCoMo launches i-Mode in Japan - considered birth of mobile phone internet services
2000s CE
Cell phones become common, social media and media streaming proliferate
Digital cameras become professionally viable
2004 CE
Voyager 1 crosses the heliosphere’s termination shock
2006 CE
Observations collected by hubble space telescope + WMAP satellite refine the age of the universe to 13.7 billion years
2010s CE
Smartphones proliferate, and eventually high-resolution cameras and media production tools become ubiquitous
2012 CE
Voyager 1 reaches the heliopause
2013 CE
Existence of the Higgs boson confirmed experimentally, completing the set for experimentally observed standard model particles
2016 CE
First detection of black hole merger via gravitation waves
2019 CE
First direct image of a black hole and its vicinity published