Vacuum energy
Quantum physics, and the widely accepted and experimentally tested Heisenberg Uncertainty Principle implies that no 'vacuum' can be truly empty. At all times, innumerable quantised 'virtual particles' must be coming into existence and then disappearing. These particles must have a collective 'mass' - or, according to Einstein's relativity theory, an equivalent energy. Calculations regarding the Universe's 'vacuum energy' vary enormously.
According to calculations that take into account the Cosmological Constantplugin-autotooltip__plain plugin-autotooltip_bigCosmological Constant Problem
The cosmological constant problem is the disagreement in 'measured' values of the cosmological constant and theoretical calculations of its value.
The cosmological constant was first proposed by Einstein as a mathematical necessity to rationalise how the universe has resisted collapsing under its own gravity. General relativity, however, predicts the, the energy should be around 10−9 joules per cubic meter.
If on the other hand the calculation is based around Quantum Electrodynamic theory and the Planck Constant, the figure is 10113 joules per cubic meter.
One (or both) of the calculations must be wrong - with an error margin of more than 120 orders of magnitude - making it the most spectacular mathematical disagreement in all of physics.
The lack of agreement has profound implications for theories of Gravityplugin-autotooltip__plain plugin-autotooltip_bigGravity
Although three of the four (known) fundamental forces have been unified by one paradigm called the Standard Model (SM) Gravity remains outside.
This doesn't necessarily mean that Standard Model has failed in some way. Perhaps Gravity is independent from and incompatible with the other three forces. (, Dark Energyplugin-autotooltip__plain plugin-autotooltip_bigDark Energy
"The observational results of the latest 15 to 20 years have established a standard model for the cosmology which has some amazing consequences. A mysterious entity, the dark energy, has been confirmed as the dominant component of the Universe, and is also responsible for its accelerated expansion., Dark Matterplugin-autotooltip__plain plugin-autotooltip_bigDark Matter
"The nature of the dominant component of galaxies and clusters remains unknown."
Source : Measuring the dark matter equation of state (Mon. Not. R. Astron. Soc. 415, L74–L77)"
In the 1930s, astronomical observations of galaxy rotations showed that the outer regions were rotating (about the galaxy's 'centre') at the same speed, or faster, than the central regions. Subsequent calculations referring to the galaxy's mass, and thus its internal gravitational attractions, showed that i…, the expansion of the Universeplugin-autotooltip__plain plugin-autotooltip_bigExpansion of the universe
unknowable
Current cosmological theory, backed up by many diverse observations, suggests that the universe is not only expanding, but that the speed of expansion is accelerating over time. Thus the limit of the observable universe is not only receding away from us (and from every other location in the universe) but the speed at which it recedes is increasing.and black holes etc etc.
See: Wikipedia
Also see: Cosmological Constant Problemplugin-autotooltip__plain plugin-autotooltip_bigCosmological Constant Problem
The cosmological constant problem is the disagreement in 'measured' values of the cosmological constant and theoretical calculations of its value.
The cosmological constant was first proposed by Einstein as a mathematical necessity to rationalise how the universe has resisted collapsing under its own gravity. General relativity, however, predicts the
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