Friedmann Equation Calculator: Hubble Parameter from Critical Density

Calculate Hubble Parameter (H)

Enter the critical mass-energy density of the universe in kilograms per cubic meter.

Explore the dynamics of the universe with our Friedmann Equation Calculator. Quickly compute the Hubble Parameter (H), a key measure of cosmic expansion, directly from the critical density (ฯc). This tool simplifies understanding the conditions for a flat universe, making complex cosmology accessible for students, researchers, and space enthusiasts.

Formula:

The Friedmann equations are fundamental in cosmology, describing the expansion of space in homogeneous and isotropic models of the universe. Our calculator uses a simplified form derived from the first Friedmann equation, focusing on the relationship between the Hubble Parameter (H) and the critical density (ρc) for a flat universe:

Formula: H = √((8πG × ρc) / 3)

Where:

  • H = Hubble Parameter (km/s/Mpc) - Describes the current expansion rate of the universe.
  • ρc = Critical density (kg/m³) - The exact mass-energy density required for a flat universe (where space is Euclidean).
  • G = Gravitational Constant (6.674 × 10โปยนยน m³/kg·s²)
  • π = Pi (approx. 3.14159)

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