Cosmological Constant

The cosmological constant (omega) is a term that was introduced by Albert Einstein in his theory of general relativity. It represents a constant energy density that is thought to permeate all of space, even in the absence of matter and radiation.

Einstein initially introduced the cosmological constant to explain the static nature of the universe, but it was later discovered that the universe is actually expanding. Despite this, the concept of the cosmological constant remained a part of Einstein's equations and was interpreted as representing the energy associated with the vacuum of space.

The cosmological constant has important implications for our understanding of the universe, including the accelerating expansion of the universe, the large-scale structure of galaxies, and the nature of dark energy. Its precise value remains a subject of ongoing research and debate in cosmology.

Three Histories

• If Omega is less than 1 (and Lambda is 0), the universe will expand forever into the big freeze.
• If Omega is greater than 1, the universe will recollapse into the big crunch.
• If Omega is equal to 1, then the universe is fat and will expand forever. (The WMAP satellite data shows that Omega plus Lambda is equal to 1, meaning that the universe is fat)

META

Status:: #wiki/notes/mature
Plantations:: Cosmology
References:: Parallel Worlds