A more conservative estimate might place the amount of dark matter at about 25 percent of the amount of luminous matter. The nearest one has been dubbed the Great Attractor; it is located at a distance of 40 megaparsecs from us. However, baryonic dark matter is a serious candidate for dark matter at least in galaxy halos, if not on larger scales.
So the expansion of the universe has not been slowing due to gravity, as everyone thought, it has been accelerating. The curve changes noticeably about 7.
The number came out times too big. As more space comes into existence, more of this energy-of-space would appear. The rotation velocities throughout many spiral galaxies have been measured, and all reveal dominance by dark matter.
As a result, this form of energy would cause the universe to expand faster and faster. Although the weakly interacting photino would be invisible, it carries off momentum that must be balanced on the other side by a detectable jet.
The problem is that there is no guarantee that these particles do exist. These experiments are of four types. One has to choose a value for the density of baryons that cannot exceed about a tenth of the critical density for closure of the universe, or too little primordial deuterium would have been synthesized.
In acknowledgment of the rivalry between these two forms of dark matter, the favored baryonic dark matter candidates have been dubbed MACHOs, for massive compact halo objects.
While this energy, some 10 to the 15 GeV, is very much higher than is directly accessible by experiment, the trend towards convergence of the disparate forces is already apparent.
In this case, the dark matter would not have shown up, since on these scales only the clumped component of the matter has been measured. In Dark matter essay to be lensed, the MACHOs must be objects that are smaller than the lens, so they must be smaller than an astronomical unit, roughly the radius of a red giant star.
The first real surprise emerges in the outermost parts of galaxies, known as galaxy halos. The relevant energy scale is not known from theory, but it must exceed GeV to avoid conflict with particle experiments. Its mass is expected to be 10 to times that of the proton.
The rotation velocity is found not to decrease with increasing distance from the galactic center. There is strong evidence for SUSY from experiments at CERN that measure the strength of the nuclear interactions, which increase with increasing energy. The big bang explanation of the light element abundances requires the existence of baryonic dark matter.
Request the removal of this essay People also read. The nature of the dark matter predicted by inflation is a profound and unresolved puzzle.
The universe is full of matter and the attractive force of gravity pulls all matter together. If the typical star near the sun was equal in mass to the sun, the ratio of total mass to total light would be unity, larger than unity if the typical star was less massive, and smaller than unity for more massive stars.
First, it is dark, meaning that it is not in the form of stars and planets that we see. It was also suggested that while this could cause a possible expansion of the universe, it was also generally agreed upon that gravity would help to keep the universe in shape and slow down its expansion.
The more shallow the curve, the faster the rate of expansion.
By now, a considerable fraction of any primordial deuterium present at the birth of the galaxy would have been destroyed inside stars. Hence, this site is written in the form of an essay.
Here, Einstein seemed to suggest that there is some strange energy-fluid filling vast part of space Hubblesite.
To estimate how much deuterium was created in the big bang, one has to factor in all the deuterium that has since been destroyed.
This is confirmed by observation: The history of the universe during the first few minutes provides an interesting measure of the total amount of baryonic matter in the universe that may help resolve the puzzle.Dark Matter Essays: OverDark Matter Essays, Dark Matter Term Papers, Dark Matter Research Paper, Book Reports.
ESSAYS, term and research papers available for UNLIMITED access. 1 Dark Matter The ultimate destiny of our expanding universe depends on how much matter it contains and whether or not the amount of matter will be enough to one day stop the expansion.
Free Essay: There is perhaps no current problem of greater importance to astrophysics and cosmology than that of "dark matter". The controversy, as. Dec 15, · Dark matter and dark energy are two entities that have very little known about them, except that they make up about 95 percent of the universe.
Even though this is a large part of the universe, it wasn’t even thought about until the ’s or the ’s. Dark Matter Essay - There is perhaps no current problem of greater importance to astrophysics and cosmology than that of "dark matter".
The controversy, as the name implies, is centered on the notion that there may exist an enormous amount of matter in the Universe that cannot be detected from the light that it emits.
The evidence of dark.
In astronomy, dark matter is a type of matter hypothesized to account for a large part of the total mass in the universe. Dark matter cannot be seen directly with telescopes; evidently it neither emits nor absorbs light or other electromagnetic radiation at any significant level.Download