Physics Constants Reference
Complete catalog of Standard Model parameters as exact fractions
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Showing 16 constants
Atmospheric Neutrino Mixing Angle
sin²θ₂₃Atmospheric neutrino oscillation parameter
Units: dimensionless
Scheme: Standard parameterization
CKM A Parameter
ACKM matrix A parameter
Units: dimensionless
Scheme: Wolfenstein parameterization
CKM Eta Bar
η̄CKM unitarity triangle apex y-coordinate
Units: dimensionless
Scheme: Wolfenstein parameterization
CKM Lambda Parameter
λCKM matrix expansion parameter
Units: dimensionless
Scheme: Wolfenstein parameterization
CKM Rho Bar
ρ̄CKM unitarity triangle apex x-coordinate
Units: dimensionless
Scheme: Wolfenstein parameterization
Dark Energy Density Parameter
Ω_ΛDark energy density fraction
Units: dimensionless
Scheme: Flat ΛCDM
Fine Structure Constant
αCoupling constant of electromagnetic interaction
Units: dimensionless
Scheme: On-shell α(0)
Hubble Constant
H₀Present-day expansion rate of the universe
Units: km s⁻¹ Mpc⁻¹
Scheme: Flat ΛCDM
Inverse Fine Structure Constant
α⁻¹Inverse of electromagnetic coupling constant
Units: dimensionless
Scheme: On-shell α(0)
Jarlskog Invariant
J_CKMMeasure of CP violation in quark sector
Units: dimensionless
Scheme: Derived from CKM parameters
Matter Density Parameter
Ω_mTotal matter density fraction
Units: dimensionless
Scheme: Flat ΛCDM
Reactor Neutrino Mixing Angle
sin²θ₁₃Reactor neutrino oscillation parameter
Units: dimensionless
Scheme: Standard parameterization
Sin 2β
sin 2βCP violation parameter in B meson decays
Units: dimensionless
Scheme: Derived from CKM parameters
Solar Neutrino Mixing Angle
sin²θ₁₂Solar neutrino oscillation parameter
Units: dimensionless
Scheme: Standard parameterization
Strong Coupling Constant
α_s(M_Z)Strong force coupling at Z boson mass
Units: dimensionless
Scheme: MS at M_Z
Weak Mixing Angle
sin²θ_WElectroweak mixing parameter
Units: dimensionless
Scheme: MS at M_Z
About These Constants
All values are represented as exact rational fractions based on the compression prior hypothesis and Minimal Description Length framework. Each constant includes its complexity score (in bits) which measures the information content required to specify the fraction.
These exact representations eliminate floating-point errors and enable perfect algebraic manipulation, making complex Standard Model calculations accessible through elementary arithmetic.