El anterior post sobre la estrella fósil nos ha llevado a repasar el concepto de ‘universo’. Es, sencillamente, ¿’todo’?. Un repaso de conceptos rápido en la wikipedia:
- Different words have been used throughout history to denote “all of space”, including the equivalents and variants in various languages of “heavens”, “cosmos“, and “world”.
- defined as the summation of all particles and energy that exist and the space-time in which all events occur-
- The currently accepted scientific theory of the universe’s formation is the Big Bang model, which describes the expansion of space-time from a gravitational singularity.
By extrapolating this expansion back in time, one approaches a gravitational singularity where everything in the universe was compressed into an infinitesimal point; an abstract mathematical concept that may or may not correspond to reality. This idea gave rise to the Big Bang theory, the dominant model in cosmology today.
- A majority of cosmologists believe that the observable universe is an extremely tiny part of the “whole” (theoretical) Universe and that it is impossible to observe the whole of comoving space
- Currently the evidence suggests not only that there is insufficient mass/energy to cause a recollapse, but that the expansion of the universe seems to be accelerating and will accelerate for eternity
- The currently observable universe appears to have a geometrically flat space-time containing the equivalent mass-energy density of 9.9 × 10-30 grams per cubic centimetre. The primary constituents appear to consist of 73% dark energy, 23% cold dark matter and 4% atoms.
- Very little is known about the size of the universe. It may be trillions of light years across, or even infinite in size.
