Cosmological constant

Cosmological constant is constant $\Lambda$ of Einstein field equation

$R_{\mu \nu }-(R/2)g_{\mu \nu }+\Lambda g_{\mu \nu }=8\pi T_{\mu \nu }$,

where $R_{\mu \nu }$ is Ricci tensor, $R$ is its contraction, $g_{\mu \nu }$ is metric tensor of spacetime, and $T_{\mu \nu }$ is stress-energy tensor.

Einstein called $\Lambda$ "the biggest blunder of my life". It turned out to be not necessary in his equation but the relativists don't know it and Einstein didn't leave any instructions about what to replace it with and that's why the relativists have still problem with this constant. I'm not credible enough even to those from my school where I'm right now doing my PhD in general realativity, to let me publish my paper "Huble redshift in Einstein's universe" demonstrating that our universe with its Hubble redshift is stationary Einstein's universe and the redshift is produced by time dilation coupled to the curvature of space.

Einstein added this cosmological constant to his field equation to make the universe stationary (neither expanding nor contracting) which it works when the cosmological constant has so called Einstein value

$\Lambda _{E}=4\pi G\rho /c^{2}$,

where $G$ is Newtonian gravitational constant, $\rho$ is density of space, and $c$ is speed of light in vacuum.