The Friedmann equations are a set of equations in physical cosmology that govern the expansion of space in homogeneous and isotropic models of the universe within the context of general relativity.They were first derived by Alexander Friedmann in 1922 from Einstein's field equations of gravitation for the Friedmann–Lemaître–Robertson–Walker metric and a perfect fluid with a given mass ...
The metric expansion of space is of a kind completely different from the expansions and explosions seen in daily life. It also seems to be a property of the universe as a whole rather than a phenomenon that applies just to one part of the universe or can be observed from "outside" it.
Just one equation relates the expansion of space to all the matter and energy we have. If you know this, you can know the fate of the Universe.
The Friedmann Equation Alexander Friedmann of Russia is credited with developing a dynamic equation for the expanding universe in the 1920s. This was a time when Einstein, Willem de Sitter of the Netherlands, and Georges Lemaitre of Belgium were also working on equations to model the universe.
These match up pretty well! So, with this assumption that the Universe is isotropic and homogeneous, there are two ways to proceed. You can — as one option — choose General Relativity as your theory of gravity, write down the spacetime that descri...
the equation that governs the expansion of the Universe. And all I need was a little bit of high school physics, geometry, and algebra. And now you know how to do it, too!
Calculating the Acceleration of the Expansion of the Universe. This is a supplementary article. To go to the main introductory article about Stationary Energy Theory, and its links to other supplementary articles, please click here.. Stationary Energy Theory’s equation for gravity gives a rate of acceleration for the expansion of the Universe that is close to the observed value
The Einstein field equations predict that the universe can expand, not that it is expanding. The fact that the universe is expanding was first observationally discovered by Edwin Hubble in 1929. Before this discovery, Einstein had introduced the cosmological constant to keep the universe from collapsing under the influence of gravity.
Expanding Universe The distant galaxies we see in all directions are moving away from the Earth, as evidenced by their red shifts. Hubble's law describes this expansion.. The fact that we see other galaxies moving away from us does not imply that we are the center of the universe!All galaxies will see other galaxies moving away from them in an expanding universe unless the other galaxies are ....
Expanding Universe. The Friedmann equation relates various cosmological parameters within the context of Einstein’s general relativity. Alexander Friedmann derived them in 1922. This famous equation states that the energy of expansion is proportional to the sum of matter energy, cosmological (vacuum) energy and curvature energy.