Fundamental Physical Constants Catalog

Physical constants of nature in SI units — the speed of light, Planck constant, elementary charge, and more — each flagged as defined-exact (post-2019 SI redefinition) or measured, with its relative standard uncertainty. Every row is read live at build time from OnlyCSharp.Data.Catalogs.PhysicsAndAstronomy.FundamentalConstants.FundamentalConstants.AllConstants. Authored as .razor; rendered to static HTML.

Sources: CODATA recommended values of the fundamental physical constants (via NIST, U.S. Government public domain, 17 U.S.C. §105) and the 2019 SI base-unit redefinition (exact defining constants). Wikipedia article slugs cross-checked per-entry. See the leaf PROVENANCE.

SymbolNameValue (SI)UnitKindRel. uncertaintyWikipedia
cspeed of light in vacuum299792458m/sexact0 (defined)Speed_of_light
hPlanck constant6.62607015E-34J·sexact0 (defined)Planck_constant
ħreduced Planck constant1.05457182E-34J·sexact0 (defined)Planck_constant
eelementary charge1.60217663E-19Cexact0 (defined)Elementary_charge
kBoltzmann constant1.380649E-23J/Kexact0 (defined)Boltzmann_constant
N_AAvogadro constant6.02214076E+23/molexact0 (defined)Avogadro_constant
g0standard acceleration of gravity9.80665m/s²exact0 (defined)Standard_gravity
Rmolar gas constant8.31446262J/(mol·K)exact0 (defined)Gas_constant
σStefan-Boltzmann constant5.67037442E-08W/(m²·K⁴)exact0 (defined)Stefan-Boltzmann_constant
eVelectron volt1.60217663E-19Jexact0 (defined)Electronvolt
GNewtonian constant of gravitation6.6743E-11m³/(kg·s²)measured2.2E-05Gravitational_constant
m_eelectron mass9.1093837E-31kgmeasured3E-10Electron_mass
m_pproton mass1.67262192E-27kgmeasured3.1E-10Proton
μ0vacuum magnetic permeability1.25663706E-06N/A²measured1.5E-10Vacuum_permeability
ε0vacuum electric permittivity8.85418781E-12F/mmeasured1.5E-10Vacuum_permittivity
αfine-structure constant0.00729735257(dimensionless)measured1.5E-10Fine-structure_constant