Wednesday, March 28, 2012
Without dark matter, the gravitational attractions at the galactic cluster scale do not work.
Without dark energy driving the universal business the expansion of the universe that is undeniably there does not work.
Not only that, these two dark things are 95% of everything to make it all work.
The cosmologists have created a mathematics that includes dark energy and dark matter and works descriptively quite well to present the universe as we know it.
Either the universe is really odd as we think it is now and we know very little, or we know almost nothing yet and something else will be in the eventual description of things.
Oh dear what can that
matter be in between things,
between the wide wheels
of heaven's carriage,
oozing between God's splay toes?
They say space doesn't
hold together right
without this invisible
stuff and yes, weeping
is called for after
March 10, 2010 2:09 PM
We believe that most of the matter in the universe is dark - it cannot be detected from the light which it emits (or fails to emit). Its presence is inferred indirectly from the motions of astronomical objects - specifically stellar, galactic, and galaxy cluster/supercluster observations. Dark matter has measurable effects on the anisotropies observed in the cosmic microwave background and plays a central role in the modeling of structure formation and galaxy evolution (shown in this NASA ESA image).
We have four lines of evidence for dark matter in cosmology: the formation of large scale structure in the length of time since decoupling requires it; the limits on the baryon density from primordial nucleosynthesis requires it; the velocities of stars within galaxies and of galaxies with clusters require it; leading theories of particle physics predict it. The cosmological effects of dark matter on cosmic structure provide one of the best windows on this physics beyond the Standard Model of particle physics.
Dark matter was postulated by Fritz Zwicky in 1934, to account for evidence of "missing mass" in the orbital velocities of galaxies in clusters. According to new supernova observations and Big Bang cosmology, dark matter accounts for 23 percent of the total mass-energy of the observable universe. Dark matter comprises about 6 times more matter than ordinary baryons do.