Wikipedia:Vital articles/Level/4/Physical sciences

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Vital articles is a list of subjects for which Wikipedia should have corresponding high-quality articles. It serves as a centralized watchlist to track the status of Wikipedia's most essential articles. This is one of eleven Level 4 sub-lists of ten thousand articles and is currently under construction.

Article in the Vital list have their assessment labelled as:

• Featured articles
• Former featured articles
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• Good articles
• Delisted good articles
• Failed good article nominees
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• Unassessed articles

The progress bar is auto-updated via category count, and the symbols and article counts are updated daily by User:cewbot. Please read the FAQ before modifying the article list.

This list is tailored to the English-language Wikipedia. There is also a list of ten thousand articles considered vital to Wikipedias of all languages.

For more information on this list and the process for adding articles please see the Frequently Asked Questions (FAQ) page.

Physical sciences (1,102 articles)

Basics (11 articles)

1. Science (Level 1)
2. Scientific method (Level 3)
3. Nature (Level 3)
4. Experiment
5. Field research
6. Laboratory
7. Observation
8. Scientific law
9. Research
10. Scientific modelling
11. Scientific theory

Measurement (69 articles)

This list contains units of measurement and articles on metrology. For the measured quantities (see the Science and Mathematics sections. For timekeeping and navigation (see the Everyday Life and Technology sections. For measurement errors (see the Statistics section in Mathematics.

General (6 articles)

1. Measurement (Level 3)
2. Accuracy and precision
3. Metrology
4. Unit of measurement
   1. Natural units
      1. Planck units

Measurement systems (4 articles)

1. Metric system
   1. International System of Units (Level 3)
2. United States customary units
3. Imperial units

Units of measurement (59 articles)

Time (7 articles)

1. Second
2. Minute
3. Hour
4. Day (Level 3)
5. Week
6. Month
7. Year (Level 3)

Dimensional space (13 articles)

Length and distance (9 articles)

1. Inch
2. Foot
3. Cubit
4. Metre
5. Mile
6. Nautical mile
7. Astronomical unit
8. Light-year
9. Parsec

Area (2 articles)

1. Acre
2. Hectare

Volume (2 articles)

1. Gallon
2. Litre

Mechanics (12 articles)

Energy, force and pressure (6 articles)

1. Atmosphere
2. Calorie
3. Electronvolt
4. Joule
5. Newton
6. Pascal

Mass (5 articles)

1. Dalton (unit)
2. Kilogram
3. Ton
4. Pound
5. Ounce

Velocity (1 article)

1. Knot

Angle (3 articles)

1. Degree
2. Radian
3. Steradian

Light (3 articles)

1. Candela
2. Lumen
3. Lux

Temperature (3 articles)

1. Celsius
2. Fahrenheit
3. Kelvin

Electromagnetism (11 articles)

1. Ampere
2. Farad
3. Coulomb
4. Henry
5. Hertz
6. Ohm
7. Siemens
8. Tesla
9. Volt
10. Watt
11. Weber

Quantity (3 articles)

Amount of substance (1 article)

1. Mole

Data (2 articles)

1. Byte
2. Bit

Radioactivity (3 articles)

1. Becquerel
2. Gray
3. Sievert

Other (1 article)

1. Decibel

Astronomy (195 articles)

For astronomical instruments, see the Optical Technology section

Basics (8 articles)

1. Astronomy (Level 2)
2. Astronomical object
3. Astrophysics
4. Extraterrestrial life

Observational astronomy (4 articles)

1. Observatory
2. Luminosity
3. Magnitude
4. Extinction

Astronomical objects (61 articles)

Solar System (25 articles)

1. Solar System (Level 2)
2. Sun (Level 2)
3. Mercury (Level 3)
4. Venus (Level 3)
5. Earth (Level 1)
   1. Moon (Level 2)
6. Mars (Level 3)
7. Asteroid belt
   1. Ceres
8. Jupiter (Level 3)
   1. Io
   2. Europa
   3. Ganymede
   4. Callisto
9. Saturn (Level 3)
   1. Enceladus
   2. Titan
10. Uranus (Level 3)
11. Neptune (Level 3)
    1. Triton
12. Kuiper belt
    1. Pluto
    2. Eris
13. Oort cloud
14. Interplanetary medium

Notable stars (10 articles)

1. Alpha Centauri
2. Arcturus
3. Betelgeuse
4. Canopus
5. Capella
6. Polaris
7. Procyon
8. Rigel
9. Sirius
10. Vega

Notable galaxies (12 articles)

1. Local Group
   1. Milky Way (Level 3)
      1. Galactic Center
         1. Sagittarius A*
   2. Andromeda Galaxy
   3. Large Magellanic Cloud
   4. Small Magellanic Cloud
   5. Triangulum Galaxy
2. Centaurus A
3. Messier 87
4. Pinwheel Galaxy
5. Whirlpool Galaxy

Notable nebulae (6 articles)

1. Carina Nebula
2. Crab Nebula
3. Eagle Nebula
4. Horsehead Nebula
5. Orion Nebula
6. Ring Nebula

Other notable objects (8 articles)

1. 3C 273
2. Cygnus X-1
3. Halley's Comet
4. Hyades
5. Omega Centauri
6. Pleiades
7. Virgo Supercluster
   1. Virgo Cluster

Celestial mechanics and astrometry (38 articles)

Celestial mechanics (17 articles)

1. Celestial mechanics
2. Orbit (Level 3)
   1. Barycenter
   2. Tidal locking
3. Eclipse
   1. Lunar eclipse
   2. Solar eclipse
4. Kepler's laws of planetary motion
5. Lagrange point
6. Night

Orbital mechanics (7 articles)

1. Orbital mechanics
2. Escape velocity
3. Geostationary orbit
4. Geosynchronous orbit
5. Gravitational acceleration
6. Gravity assist
7. Low Earth orbit

Celestial sphere (8 articles)

1. Celestial sphere
2. Astronomical coordinate systems
   1. Equatorial coordinate system
3. Equinox
4. Ecliptic
5. Horizon
6. Solstice
7. Zodiac

Constellations (8 articles)

1. Constellation
   1. Canis Major
   2. Cassiopeia
   3. Centaurus
   4. Crux
   5. Orion
   6. Ursa Major
   7. Ursa Minor

Astrometry (5 articles)

1. Astrometry
2. Albedo
3. Cosmic distance ladder
4. Parallax
5. Photometry

Galactic astronomy and extragalactic astronomy (27 articles)

Basics (15 articles)

1. Outer space (Level 3)
2. Galaxy (Level 3)
3. Black hole (Level 3)
   1. Event horizon
   2. Supermassive black hole
4. Galaxy groups and clusters
   1. Supercluster
5. Interstellar medium
6. Nebula
7. Dark nebula
8. Molecular cloud
9. Great Attractor
10. H II region
11. Void (astronomy)
12. Cosmic ray

Galaxy morphological classification (7 articles)

1. Galaxy morphological classification
2. Spiral galaxy
   1. Barred spiral galaxy
3. Elliptical galaxy
4. Lenticular galaxy
5. Irregular galaxy
6. Dwarf galaxy

Active galactic nucleus (5 articles)

1. Active galactic nucleus
   1. Blazar
   2. Quasar
   3. Radio galaxy
   4. Seyfert galaxy

Physical cosmology (16 articles)

1. Physical cosmology (Level 3)
2. Universe (Level 2)
   1. Observable universe
   2. Chronology of the universe
      1. Ultimate fate of the universe
3. Big Bang (Level 3)
   1. Inflation (cosmology)
   2. Cosmic microwave background
4. Galaxy formation and evolution
5. Formation and evolution of the Solar System
   1. Nebular hypothesis
6. Dark matter
7. Dark energy
   1. Cosmological constant
8. Redshift
   1. Hubble's law

Planetary science (14 articles)

1. Planet (Level 3)
   1. Terrestrial planet
   2. Giant planet
   3. Exoplanet
2. Natural satellite (Level 3)
3. Comet (Level 3)
4. Minor planet
   1. Asteroid (Level 3)
   2. Dwarf planet
   3. Meteoroid
5. Atmosphere
6. Meteor shower
7. Impact event
8. Ring system

Stellar astronomy (31 articles)

1. Star (Level 3)
2. Variable star
   1. Supernova (Level 3)
      1. Gamma-ray burst
   2. Nova
   3. Pulsar
   4. Cepheid variable
3. Star system
   1. Planetary system
   2. Binary star
   3. Star cluster
4. Stellar classification
5. Stellar evolution
   1. Star formation
      1. Starburst galaxy
   2. Planetary nebula
   3. Protostar
   4. Main sequence
   5. Giant star
      1. Red giant
   6. Supergiant
   7. Wolf–Rayet star
   8. White dwarf
   9. Neutron star
6. Stellar kinematics
7. Stellar magnetic field
8. Stellar structure
9. Solar wind
10. Metallicity
11. Brown dwarf
12. Hertzsprung–Russell diagram

Chemistry (272 articles)

For biochemistry and chemical biology see the Biology and health sciences section; for chemical industry see the Technology section

General (23 articles)

1. Chemistry (Level 2)
2. Organic chemistry (Level 3)
3. Inorganic chemistry (Level 3)
4. Physical chemistry (Level 3)
5. Electrochemistry
   1. Electrolysis
6. Environmental chemistry
7. Medicinal chemistry
8. Nuclear chemistry
   1. Nuclide
9. Organometallic chemistry
10. Phase diagram
11. Photochemistry
12. Polymer chemistry
    1. Polymer
13. Quantum chemistry
14. Materials science
15. Alchemy
16. Chemical substance
    1. Amount of substance
17. Chemical synthesis
18. Conservation of mass
19. pH

Chemical reactions (14 articles)

1. Chemical reaction (Level 3)
   1. Acid–base reaction (Level 3)
   2. Catalysis (Level 3)
   3. Chemical equation
   4. Chemical equilibrium
   5. Chemical formula
   6. Chemical kinetics
   7. Combustion
   8. Corrosion
      1. Redox (Level 3)
   9. Haber process
   10. Radical
   11. Reaction mechanism
   12. Substitution reaction

Chemical bonds (8 articles)

1. Chemical bond (Level 3)
   1. Molecule (Level 3)
   2. Ionic bonding
   3. Covalent bond
   4. Metallic bonding
   5. Intermolecular force
      1. Hydrogen bond
   6. Valence bond theory

Separation processes (3 articles)

1. Chromatography
2. Distillation
3. Filtration

Analytical chemistry (4 articles)

1. Analytical chemistry
2. Spectroscopy
   1. Absorption spectroscopy
3. Mass spectrometry

Chemical substances (220 articles)

Chemical elements (117 articles)

Basics (5 articles)

1. Chemical element (Level 2)
2. Periodic table (Level 3)
3. Allotropy
4. Atomic number
5. Atomic mass

Chemical element groups (10 articles)

1. Metal (Level 3)
2. Alkali metal
3. Alkaline earth metal
4. Lanthanide
5. Actinide
6. Transition metal
7. Metalloid
8. Halogen
9. Noble gas
10. Synthetic element

Chemical elements (102 articles)

1. Hydrogen (Level 3)
2. Helium
3. Lithium
4. Beryllium
5. Boron
6. Carbon (Level 3)
   1. Diamond
   2. Graphite
   3. Carbon nanotube
7. Nitrogen (Level 3)
8. Oxygen (Level 3)
   1. Ozone
9. Fluorine
10. Neon
11. Sodium
12. Magnesium
13. Aluminium (Level 3)
14. Silicon (Level 3)
15. Phosphorus (Level 3)
16. Sulfur (Level 3)
17. Chlorine
18. Argon
19. Potassium
20. Calcium
21. Scandium
22. Titanium
23. Vanadium
24. Chromium
25. Manganese
26. Iron (Level 3)
27. Cobalt
28. Nickel
29. Copper (Level 3)
30. Zinc
31. Gallium
32. Germanium
33. Arsenic
34. Selenium
35. Bromine
36. Krypton
37. Rubidium
38. Strontium
39. Yttrium
40. Zirconium
41. Niobium
42. Molybdenum
43. Technetium
44. Ruthenium
45. Rhodium
46. Palladium
47. Silver (Level 3)
48. Cadmium
49. Indium
50. Tin
51. Antimony
52. Tellurium
53. Iodine
54. Xenon
55. Caesium
56. Barium
57. Lanthanum
58. Cerium
59. Praseodymium
60. Neodymium
61. Promethium
62. Samarium
63. Europium
64. Gadolinium
65. Terbium
66. Dysprosium
67. Holmium
68. Erbium
69. Thulium
70. Ytterbium
71. Lutetium
72. Hafnium
73. Tantalum
74. Tungsten
75. Rhenium
76. Osmium
77. Iridium
78. Platinum
79. Gold (Level 3)
80. Mercury (element)
81. Thallium
82. Lead
83. Bismuth
84. Polonium
85. Astatine
86. Radon
87. Francium
88. Radium
89. Actinium
90. Thorium
91. Protactinium
92. Uranium
93. Neptunium
94. Plutonium
95. Americium
96. Curium
97. Berkelium
98. Californium

Chemical compounds (85 articles)

General (3 articles)

1. Chemical compound (Level 3)
   1. Inorganic compound
   2. Organic compound

Inorganic compounds (22 articles)

1. Water (Level 2)
   1. Properties of water
   2. Ice
   3. Water vapor
2. Oxide
   1. Carbon dioxide (Level 3)
   2. Carbon monoxide
   3. Nitrous oxide
   4. Titanium dioxide
3. Hydrogen peroxide
4. Cyanide
5. Acid
   1. Boric acid
   2. Hydrochloric acid
   3. Hydrofluoric acid
   4. Nitric acid
   5. Phosphoric acid
   6. Sulfuric acid
6. Base
   1. Ammonia
   2. Potassium hydroxide
   3. Sodium hydroxide

Salts (20 articles)

1. Salt (chemistry)
2. Carbonate
   1. Calcium carbonate
   2. Sodium bicarbonate
   3. Sodium carbonate
3. Chloride
   1. Calcium chloride
   2. Polyvinyl chloride
   3. Sodium chloride
4. Nitrate
   1. Ammonium nitrate
   2. Potassium nitrate
   3. Sodium nitrate
5. Silicate
   1. Sodium silicate
6. Sulfate
   1. Alum
   2. Sodium sulfate
   3. Ammonium sulfate
   4. Magnesium sulfate

Organic compounds (6 articles)

1. Haloalkane
2. Organophosphorus chemistry
3. Organosilicon chemistry
   1. Silicone
4. Organosulfur chemistry
   1. Thiol

Carbon–nitrogen bond (4 articles)

1. Amide
   1. Urea
   2. Nylon
2. Amine

Carbon–oxygen bond (16 articles)

1. Alcohol
   1. Ethanol
   2. Methanol
2. Aldehyde
   1. Formaldehyde
3. Carboxylic acid
   1. Acetic acid
   2. Citric acid
   3. Lactic acid
4. Ester
   1. Polyester
5. Ether
6. Ketone
   1. Acetone
7. Phenol
   1. Tannin

Hydrocarbons (14 articles)

1. Hydrocarbon
2. Alkane
   1. Butane
   2. Ethane
   3. Methane
   4. Propane
3. Alkene
   1. Ethylene
      1. Polyethylene
   2. Propylene
      1. Polypropylene
4. Aromatic compound
   1. Benzene
5. Alkyne

Chemical mixtures (18 articles)

General (12 articles)

1. Alloy (Level 3)
2. Mixture
3. Aerosol
4. Amalgam
5. Colloid
6. Dispersion
7. Emulsion
8. Foam
9. Gel
10. Solution
11. Suspension
12. Syngas

Specific alloys (6 articles)

1. Brass
2. Bronze (Level 3)
3. Cast iron
4. Steel (Level 3)
   1. Stainless steel
5. Wrought iron

Earth science (262 articles)

For specific geographical objects see Geography

Basics (2 articles)

1. Earth science (Level 3)
2. Natural resource

Natural disasters (8 articles)

1. Natural disaster
2. Earthquake (Level 3)
3. Flood (Level 3)
4. Drought
5. Avalanche
6. Landslide
7. Tsunami
8. Wildfire

Earth (164 articles)

General (1 article)

1. Internal structure of Earth (Level 3)

Geology (52 articles)

1. Geology (Level 2)
2. Plate tectonics (Level 3)
3. Fold
4. Stratigraphic unit
5. Meteorite
   1. Impact crater
6. Lithosphere
   1. Crust
   2. Fault
7. Stratigraphy
8. Thrust fault

Mineralogy (11 articles)

1. Mineral (Level 3)
2. Mineralogy
3. Gemstone
4. Feldspar
5. Kaolinite
6. Pyroxene
7. Quartz
8. Talc
9. Mica
10. Gypsum
11. Asbestos

Mineral gemstones (4 articles)

1. Emerald
2. Jade
3. Sapphire
4. Ruby

Organic gemstones (3 articles)

1. Amber
2. Ivory
3. Pearl

Petrology (23 articles)

1. Petrology
2. Rock (Level 3)
   1. Ore
3. Igneous rock
   1. Basalt
   2. Granite
   3. Magma
   4. Tuff
4. Sedimentary rock
   1. Limestone
   2. Clay
   3. Sand
   4. Oil shale
   5. Sandstone
   6. Bauxite
5. Metamorphic rock
   1. Schist
   2. Marble
   3. Gneiss
   4. Slate
6. Conglomerate
7. Breccia
8. Gravel

Geophysics (7 articles)

1. Geodesy
2. Geophysics
3. Earth's inner core
4. Earth's magnetic field
5. Earth's outer core
6. Mantle
7. Seismology

Geomorphology (50 articles)

1. Geomorphology
2. Erosion (Level 3)
3. Weathering

Landforms (11 articles)

1. Landform
2. Land (Level 2)
3. Continent (Level 3)
4. Mountain (Level 3)
5. Mountain range
6. Hill
7. Valley
8. Plateau
9. Mesa
10. Plain
11. Sedimentary basin

Fluvial landforms (9 articles)

1. Alluvial fan
2. Beach
3. Canyon
4. Cliff
5. Floodplain
6. Meander
7. Oasis
8. Rapids
9. Waterfall

Glacial landforms (3 articles)

1. Glacial landform
2. Fjord
3. Moraine

Caves (2 articles)

1. Cave
2. Karst

Oceanic and coastal landforms (12 articles)

1. Abyssal plain
2. Archipelago
3. Bay
4. Coast
5. Continental shelf
6. Coral reef
   1. Atoll
7. Lagoon
8. Oceanic trench
9. Peninsula
10. Island (Level 3)
11. Seamount

Volcanic landforms (5 articles)

1. Volcano (Level 3)
2. Geyser
3. Hotspot
4. Lava
5. Mid-ocean ridge

Aeolian landforms (2 articles)

1. Aeolian processes
2. Dune

Artificial landforms (3 articles)

1. Artificial island
2. Land reclamation
3. Polder

Geological history (28 articles)

1. History of Earth (Level 3)
   1. Geological history of Earth
2. Geochronology
3. Geologic time scale
4. Great Oxidation Event
5. Cambrian explosion
6. Extinction event
   1. Late Ordovician mass extinction
   2. Late Devonian extinction
   3. Permian–Triassic extinction event
   4. Triassic–Jurassic extinction event
   5. Cretaceous–Paleogene extinction event
7. Ice age
8. Pangaea

Geological periods (14 articles)

1. Precambrian
2. Phanerozoic
   1. Paleozoic
      1. Cambrian
      2. Permian
   2. Mesozoic
      1. Triassic
      2. Jurassic
      3. Cretaceous
   3. Cenozoic
      1. Paleogene
      2. Neogene
      3. Quaternary
         1. Holocene

Biomes (19 articles)

1. Desert (Level 3)
2. Tundra
3. Shrubland

Forests (7 articles)

1. Forest (Level 3)
2. Jungle
3. Mangrove
4. Taiga
5. Rainforest
   1. Tropical rainforest
6. Temperate broadleaf and mixed forests

Grasslands (5 articles)

1. Grassland (Level 3)
2. Meadow
3. Prairie
4. Savanna
5. Steppe

Wetlands (4 articles)

1. Wetland
2. Swamp
3. Marsh
4. Bog

Pedology (7 articles)

1. Soil (Level 3)
   1. Peat
2. Soil formation
3. Pedosphere
4. Sediment
5. Soil fertility
6. Soil science

Air (59 articles)

Atmosphere (9 articles)

1. Atmosphere of Earth (Level 3)
2. Air mass
3. Atmospheric pressure
4. Atmospheric science
5. Ozone depletion

Atmospheric optics (4 articles)

1. Aurora
2. Mirage
3. Rainbow
4. Sky

Climatology (9 articles)

1. Climatology
2. Climate (Level 2)
3. Climate change (Level 3)
   1. Greenhouse effect
4. Climate variability and change
5. El Niño–Southern Oscillation
6. Köppen climate classification
7. Temperate climate
8. Tropical climate

Meteorology (41 articles)

General (6 articles)

1. Meteorology
2. Weather (Level 3)
3. Weather front
4. Weather forecasting
5. Humidity
6. Low-pressure area

Clouds (5 articles)

1. Cloud (Level 3)
2. Cirrus cloud
3. Cumulonimbus cloud
4. Cumulus cloud
5. Fog

Precipitation (7 articles)

1. Precipitation
2. Rain (Level 3)
3. Snow (Level 3)
4. Acid rain
5. Hail
6. Dew
7. Frost

Seasons (5 articles)

1. Season (Level 3)
2. Spring (season)
3. Summer
4. Autumn
5. Winter

Atmospheric circulation (7 articles)

1. Atmospheric circulation
2. Anticyclone
3. Cyclone
4. Extratropical cyclone
5. Hadley cell
6. Polar vortex
7. Walker circulation

Storms (7 articles)

1. Storm
2. Tornado (Level 3)
3. Tropical cyclone (Level 3)
4. Blizzard
5. Dust storm
6. Lightning
7. Thunderstorm

Winds (4 articles)

1. Wind (Level 3)
2. Jet stream
3. Monsoon
4. Trade winds

Water (29 articles)

General (2 articles)

1. Hydrosphere
2. Cryosphere

Glaciology (6 articles)

1. Glacier (Level 3)
2. Ice sheet
3. Ice shelf
4. Iceberg
5. Sea ice
6. Permafrost

Oceanography (8 articles)

1. Oceanography
2. Sea (Level 2)
3. Ocean
4. Tide
5. Sea level
6. Seabed
7. Ocean current
8. Thermohaline circulation

Hydrology (13 articles)

1. Hydrology
2. Water cycle
3. Groundwater
   1. Spring (hydrology)
4. Hydrography
5. Limnology
6. Lake (Level 3)
   1. Dry lake
   2. Pond
7. River (Level 3)
   1. Drainage basin
   2. Estuary
   3. River delta

Physics (293 articles)

Basics (23 articles)

1. Physics (Level 2)
2. Energy (Level 2)
   1. Conservation of energy
3. Matter (Level 3)
   1. Atom (Level 2)
4. Force (Level 3)
   1. Electromagnetism (Level 3)
   2. Gravity (Level 3)
   3. Strong interaction (Level 3)
   4. Weak interaction (Level 3)
5. Spacetime
   1. Space (Level 3)
      1. Vacuum (Level 3)
   2. Time (Level 2)
6. Mass–energy equivalence
7. Quantum gravity
8. Radiation
   1. Ionizing radiation
9. Field (physics)
   1. Flux
10. Gauge theory
11. Symmetry (physics)
12. Theoretical physics

Atomic, molecular and optical physics (23 articles)

Atomic physics (13 articles)

1. Atomic physics
2. Atomic nucleus
3. Atomic orbital
4. Atomic theory
5. Binding energy
6. Bohr model
7. Bremsstrahlung
8. Electron configuration
9. Electron shell
10. Energy level
11. Geiger–Marsden experiments
12. Ion
13. Isotope

Molecular physics (2 articles)

1. Molecular orbital
2. Molecular orbital theory

Optics (8 articles)

1. Optics (Level 3)
2. Focus
   1. Focal length
3. Polarization
4. Reflection
5. Refraction
   1. Refractive index
6. Transparency and translucency

Color (17 articles)

Basics (6 articles)

1. Color (Level 3)
2. CMYK color model
3. Color theory
   1. Primary color
4. Gloss (optics)
5. RGB color model

Color terms (11 articles)

1. White
2. Black
3. Grey
4. Red
5. Orange
6. Yellow
7. Green
8. Blue
9. Pink
10. Purple
11. Brown

Condensed matter physics (25 articles)

Basics (3 articles)

1. Condensed matter physics
2. Solid-state physics
3. Amorphous solid

Crystallography (3 articles)

1. Crystallography
2. Crystal
3. Crystallization

States of matter (8 articles)

1. State of matter (Level 3)
2. Solid
3. Liquid
4. Gas
   1. Vapor
5. Plasma
6. Degenerate matter
7. Bose–Einstein condensate

Phase transitions (11 articles)

1. Phase transition
2. Phase
3. Boiling
4. Melting
5. Freezing
6. Evaporation
7. Condensation
8. Ionization
9. Sublimation
10. Critical point
11. Triple point

Electromagnetism (45 articles)

Basics (10 articles)

1. Electricity (Level 2)
2. Magnetism (Level 3)
   1. Ferromagnetism
3. Magnet
   1. Electromagnet
4. Dielectric
5. Dipole
6. Metamaterial
7. Oil drop experiment
8. Photoelectric effect

Electrostatics (5 articles)

1. Electrostatics
2. Coulomb's law
3. Electric charge
4. Electric field
5. Electric potential

Electrodynamics (15 articles)

1. Electromagnetic radiation (Level 3)
   1. Electromagnetic spectrum
   2. Radio wave
   3. Microwave
   4. Infrared
   5. Visible spectrum
   6. Ultraviolet
   7. X-ray
   8. Fluorescence
2. Electromagnetic field
3. Electromagnetic induction
4. Electromotive force
5. Lorentz force
6. Eddy current
7. Maxwell's equations

Magnetism (2 articles)

1. Magnetic field
2. Magnetostatics

Electrical circuits (13 articles)

1. Electric current
   1. Alternating current
   2. Direct current
2. Electrical network
3. Electrical impedance
4. Electrical resistance and conductance
5. Capacitance
   1. Ohm's law
6. Semiconductor
7. Superconductivity
8. Gain (electronics)
9. Inductance
10. Kirchhoff's circuit laws

Mechanics (77 articles)

Basics (10 articles)

1. Mechanics
   1. Ballistics
   2. Continuum mechanics
   3. Dynamics
   4. Kinematics
   5. Relativistic mechanics
   6. Statics
2. Oscillation
   1. Harmonic oscillator
      1. Simple harmonic motion

Quantum mechanics (11 articles)

1. Quantum mechanics (Level 3)
2. Pauli exclusion principle
3. Quantum chromodynamics
4. Quantum electrodynamics
5. Quantum entanglement
6. Quantum field theory
7. Quantum tunnelling
8. Schrödinger equation
9. Uncertainty principle
10. Wave function
11. Wave–particle duality

Classical mechanics (29 articles)

1. Classical mechanics (Level 3)
   1. Hamiltonian mechanics
   2. Lagrangian mechanics
2. Mass (Level 3)
   1. Density
3. Momentum (Level 3)
4. Motion (Level 3)
   1. Newton's laws of motion (Level 3)
   2. Speed
   3. Acceleration
   4. Velocity
   5. Equations of motion
5. Kinetic energy
6. Potential energy
7. Inertia
8. Moment of inertia
9. Friction
10. Impulse
11. Power
12. Work
13. Rotation
    1. Angular momentum
    2. Centripetal force
    3. Coriolis force
14. Torque
15. Weight
    1. Weighing scale
16. Frame of reference
17. Newton's law of universal gravitation

Fluid mechanics (16 articles)

1. Fluid mechanics
2. Fluid dynamics
   1. Aerodynamics
3. Bernoulli's principle
4. Buoyancy
5. Convection
6. Drag
7. Diffusion
8. Flight
9. Lift (force)
10. Navier–Stokes equations
11. Osmosis
12. Reynolds number
13. Surface tension
14. Turbulence
15. Viscosity

Solid mechanics (10 articles)

1. Solid mechanics
2. Deformation
3. Elastic modulus
4. Elasticity
5. Fatigue
6. Hooke's law
7. Plasticity
8. Stiffness
9. Strength of materials
10. Stress (mechanics)

Statistical mechanics (1 article)

1. Statistical mechanics

Nuclear physics (8 articles)

1. Nuclear physics
2. Nuclear fission
3. Nuclear fusion
4. Nucleosynthesis
5. Radioactive decay (Level 3)
   1. Alpha particle
   2. Beta particle
   3. Gamma ray

Particle physics (35 articles)

General (13 articles)

1. Particle physics (Level 3)
2. Standard Model (Level 3)
3. Physics beyond the Standard Model
   1. String theory
   2. Supersymmetry
4. Particle
5. Particle accelerator
   1. Large Hadron Collider
   2. Tevatron
6. Particle detector
7. Cloud chamber
8. Scattering
9. Spin

Subatomic particles (19 articles)

1. Subatomic particle (Level 3)

Fermions (12 articles)

1. Fermion
2. Lepton
   1. Electron (Level 3)
   2. Muon
   3. Tau
   4. Neutrino
3. Quark
4. Hadron
   1. Baryon
      1. Neutron (Level 3)
      2. Proton (Level 3)
   2. Meson

Bosons (6 articles)

1. Boson
2. Gauge boson
   1. Photon (Level 3)
   2. Gluon
   3. W and Z bosons
3. Higgs boson

Antimatter (3 articles)

1. Antimatter
2. Antiparticle
   1. Positron

Theory of relativity (8 articles)

1. Theory of relativity (Level 3)
2. General relativity
3. Special relativity
4. Principle of relativity
5. Equivalence principle
6. Gravitational wave
7. Lorentz transformation
8. Michelson–Morley experiment

Thermodynamics (15 articles)

1. Thermodynamics (Level 3)
2. Heat (Level 3)
3. Temperature (Level 3)
   1. Absolute zero
4. Pressure
5. Laws of thermodynamics
6. Heat capacity
7. Heat transfer
8. Entropy
9. Enthalpy
10. Black-body radiation
11. Internal energy
12. Thermodynamic cycle
13. Thermodynamic free energy
14. Ideal gas law

Waves (17 articles)

1. Wave (Level 3)
2. Light (Level 3)
   1. Speed of light (Level 3)
3. Acoustics
   1. Sound (Level 3)
      1. Speed of sound
   2. Ultrasound
4. Amplitude
5. Frequency
6. Wavelength
7. Diffraction
8. Doppler effect
9. Wave interference
10. Noise
11. Resonance
12. Superposition principle
13. Wave equation