Cold dark matter
Cold dark matter (or CDM) is a refinement of the big bang theory that contains the additional assumption that most of the matter in the Universe consists of material which cannot be observed by its electromagnetic ...
Cold dark matter is a refinement of the big bang theory that contains the additional assumption that most of the matter in the Universe consists of material that cannot be observed by its electromagnetic radiation and hence is dark while at ...
cold dark matter Class of dark-matter candidates made up of very heavy particles, such as supersymmetric relics.
cold dark matter: Invisible matter in the universe composed by heavy, slow-moving particles such as WIMPs.
collapsar: See hypernova.
COLD DARK MATTER (CDM) - Non-relativistic and non-luminous matter that likely contributes significantly to the density of galaxies and of the universe as a whole (but does not close the universe).
Cold Dark Matter (CDM)
(a) Hypothetical subatomic particles that move slowly compared with the speed of light.
(b) Any dark matter candidate which was non-relativistic at the point of decoupling.
Cold Dark Matter. [HH98]
CD-ROM
Compact Disk - Read Only Memory A computer data storage technology.
Cold dark matter is the model where the dark matter is explained as being cold (i.e. its velocity is non-relativistic (vnon-baryonic, dissipationless (can not cool by radiating photons) and collisionless (i.e.
cold dark matter Hypothetical class of dark-matter candidates made up of slow-moving subatomic particles, such as supersymmetric relics of a very early stage of the Big Bang.
Cold dark matter
Baryonic dark matter
Hot dark matter consists of particles that travel with relativistic velocities. One kind of hot dark matter is known, the neutrino.
The cold dark matter theory, which holds that around 75 percent of the Universe's matter is made of mysterious, invisible dark matter, has long been used to explain how the initially smooth Universe born 13.
Theory makes a convenient distinction between hot and cold dark matter, where HDM is relativistic and therefore doesn't fall easily into galaxy-sized potential wells, ...
Currently most astronomers who are trying to figure out what the Universe is like have been using the cold dark matter theory to model the growth of structures in the Universe.
The popular "cold dark matter" theory predicts that exotic dark matter (of a yet unknown and undetectable nature) and a little bit of normal matter (the stuff that the stars and ourselves are made of) clumped together to form long filaments, ...
is made of elementary particles that played a key role in the formation of the universe, possibly the low-mass neutrino or theoretical particles called axions and WIMPs [Weakly Interacting Massive Particles]; these are the so-called cold dark matter ...
Extrapolating from their results, their results indicate that about 80 percent of the total amount of matter in the Universe consists of a form of dark matter called "cold dark matter" - to distinguish it from "hot dark matter". Cold? Hot?
The non-baryonic forms are usually subdivided into two classes - Hot Dark Matter (HDM) and Cold Dark Matter (CDM). HDM requires a particle with near-zero mass (neutrinos are a prime example; axions, or supersymmetric particles are others).
However, the Milky Way is surrounded by a "halo" of cold dark matter, which produces no detectable energy but that reveals its presence by exerting a gravitational pull on the visible matter around it.
Most current models are based on the notion of cold dark matter which has supplanted other models of hot dark matter and baryonic matter.
"Our measurements contradict a basic prediction about the structure of cold dark matter in dwarf galaxies. Unless or until theorists can modify that prediction, cold dark matter is inconsistent with our observational data," Walker stated.
- "Baryonic" matter, ie normal matter makes only 4% ( yes you read correctly: f-o-u-r per cent ) of the universe, 23% is an exotic version of matter they call cold dark matter and 73% is even more mysterious dark energy that could account for the ...
A Dictionary of Astronomy entry for hot dark matter
A Dictionary of Astronomy entry for cold dark matter
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The prevailing 'Cold Dark Matter' model predicts that our own Milky Way galaxy is surrounded by hundreds of dark matter clumps, each a few hundred light years in size and possibly populated by a dwarf galaxy.
Axions would be able efficiently to transport energy out of stars or out of supernova cores. They have also become candidates to explain cold dark matter.
It was from density fluctuations (or anisotropic irregularities) in this primordial matter that larger structures began to appear. As a result, masses of baryonic matter started to condense within cold dark matter halos.
 See also: Dark Matter, Universe, Galaxies, Gravitation, Mass
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