The simplest resolution is to put the

cosmological constant back into Einstein's equation.

But it looks like the favorite theory is one that has long been sidelined - that of the

cosmological constant, introduced by Albert Einstein (who else?

where [XI]/2 is the variation of

cosmological constant [LAMBDA].

We also discuss the

cosmological constant in these spacetimes.

Einstein, in order to obtain static universe, had earlier introduced the term with the

cosmological constant.

Possibly, Jason, when he needlessly added a

cosmological constant to his theory of relativity to account for a quasi-static distribution of matter as required by the velocity of stars, unaware that the universe was in fact expanding.

The simplest form of DE compatible with the data, a

cosmological constant, has a value incompatible with our understanding of Quantum Field Theory.

In the ACDM model, the role of DE is played by the

cosmological constant A (vacuum energy), but this model has two main problems: the fine tuning problem and the coincidence problem [7].

So Einstein altered his equation, adding a factor called the

cosmological constant, representing a constant energy density in space that kept the universe static.

Adding to gravity and repulsion the

cosmological constant (repulsion) on a "gravitational field equation" of space-time warpage, Einstein built another mechanical worldview.

Developed by Cai and Zhang [25], these represent static, plane-symmetric solutions of the Einstein-Maxwell equations with a negative

cosmological constant.

Chapter 5, "The Goldilocks Enigma" (a phrase used by Paul Davies in connection with the "just right for life" character of the universe), sets out twelve examples of the apparent fine-tuning of the universe, including the ratio of the electromagnetic and strong interaction strengths, the value of the

cosmological constant, and the dimensionality of space.