Static universe

In

In contrast to this model, Albert Einstein proposed a temporally infinite but spatially finite model - static eternal universe - as his preferred cosmology during 1917, in his paper Cosmological Considerations in the General Theory of Relativity.

After the discovery of the

The Einstein universe

During 1917, Albert Einstein added a positive

This motivation ended after the proposal by the astrophysicist and Roman Catholic priest

with value precisely ${\displaystyle \Lambda _{E}=4\pi G\rho /c^{2}}$, where ${\displaystyle G}$ is Newtonian gravitational constant, ${\displaystyle \rho }$ is the energy density of the matter in the universe and ${\displaystyle c}$ is the

radius of curvature

of space of the Einstein universe is equal to

${\displaystyle R_{E}=\Lambda _{E}^{-1/2}={c \over {\sqrt {4\pi G\rho }}}.}$

The Einstein universe is one of Friedmann's solutions to Einstein's field equation for dust with density ${\displaystyle \rho }$, cosmological constant ${\displaystyle \Lambda _{E}}$, and radius of curvature ${\displaystyle R_{E}}$. It is the only non-trivial static solution to Friedmann's equations.^{[citation needed]}

Because the Einstein universe soon was recognized to be inherently unstable, it was presently abandoned as a viable model for the universe. It is unstable in the sense that any slight change in either the value of the cosmological constant, the

After Einstein renounced his cosmological constant, and embraced the Friedmann-LeMaitre model of an expanding universe,

• Milne model
• Steady State theory
• Plasma cosmology

References