Friedmann equations govern cosmic expansion in homogeneous and isotropic models
Friedmann equations
Friedmann equations govern cosmic expansion in homogeneous and isotropic models
The FLRW models, built on the Friedmann equations, form the Standard Model of modern cosmology, showing their foundational role in our understanding of the universe. These models are further refined in the Lambda-CDM model, which incorporates dark energy and cold dark matter, illustrating the evolution and complexity of cosmological theories over time.
Example
The Friedmann equation for a flat universe (k=0) is given by H^2 = (8πG/3)ρ - (kc^2)/a^2 + Λc^2/3, where H is the Hubble parameter, G is the gravitational constant, ρ is the mass density, a is the scale factor, k is the curvature parameter, c is the speed of light, and Λ is the cosmological constant.
Understanding the Friedmann equations is crucial for predicting the future behavior of the universe and for developing new theories in cosmology.
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