dark energy
An as yet unknown and unidentified form of energy that pervades the universe and produces a force that counteracts the gravitational attraction between galaxies.
# Dark energy is thought to be responsible for the accelerating universe.
2006-09-09 01:19:54
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answer #1
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answered by Anonymous
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Black Hole: A star that has collapsed due to its own gravity to the place that light cannot escape from the gravity well. These are typically discovered by measuring the mass by looking at things orbiting them and noticing that there isn't enough space for all that mass unless it is a black hole. There are large black holes in the centers of many galaxies and smaller black holes from supernova explosions.
Dark Mass: When we model the way stars orbit galaxies we find that there is more mass there than can be seen. This mass also bends light that goes by forming gravitational lenses. The amount of mass is about 7 times the amount of ordinary matter. Some scientists propose that this dark matter is made of subatomic particles predicted by supersymmetry, but nobody really knows.
Dark Energy: it turns out that the universe is not only expanding, but the rate of that expansion is accelerating. In order for this to happen, there has to be a substance that maintains its density even through that expansion. This means it is more a property of space itself than a real substance. It is called Dark Energy.
There are active many research programs to study black holes and dark matter. Accelerator projects are trying to make the supersymmetric particles that may explain dark matter. Astronomers are mapping out the distribution of it. As for Dark Energy, we have very few clues at this point as to what it is. But we know it makes up 3 times as much of the universe as regular matter and dark matter combined.
Mysteries are always interesting.
2006-09-09 03:01:31
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answer #2
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answered by mathematician 7
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Many answers above tells what they are. Mathematician gave a good answer.
Analysis.
The dark matter and dark energies are in existence only in scientists equation. That is on one side they get huge mass presence calculated from the observed gravity etc. on the other hand the actual or estimated mass or matter form other observation. They don't match. There is a large discrepancy. Scientists came up with this pseudo dark matter and dark energy. These may disappear or reduce in quantity once we have improved out estimation and observation process.
On the other hand the black holes are real but not holes. They are huge chunk of mass creating very large gravity
2006-09-09 03:17:43
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answer #3
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answered by Dr M 5
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It is likely you could define these values as well as anyone else. They are theoretical. "Dark energy & matter" are terms used by people who are in the dark about what they seek. The words they use do not specifically define the problem, rather "interpertive", non-specific words are used in order that a general meaning may be given to the concept. Sorta like using the term "nice weather". Anything can fit into the thought.
Concerning "black holes," they are an impossibility. The evidence for this is determining the acceleration of a mass within earth that is 0.716 miles outward from the very core of our planet. Were it able to be released in this location to freely fall, it would exceed the speed of light in one second. In our sun, this distance is 400 miles from its center.
If the concept of "black holes" were a valid concept, these should exist within our planet, and especially within the sun. There is a short writing, "The Problem and Repair of Relativity" at http://360.yahoo.com/noddarc that explains why this is true.
2006-09-09 06:22:53
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answer #4
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answered by Anonymous
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well, they're very important because, surprisingly enough, they make up MOST of the matter and energy that our universe is made out of. that's important to know when we try to figure out the nature of the universe, how it formed, and what it's doing now. we can only actually see and detect less than half of what's out there (we only know it's there by watching how the stuff we *can* see reacts to it). nobody really knows what they are, yet, tho scientists are trying very hard to figure it out. they're very popular right now because some exciting discoveries about how much there is and where have been made recently. black holes are something different, we can detect them just fine, and they used to be perfectly ordinary stars. after the star burns out, it collapses in on itself into an incredibly heavy, tiny ball of matter, with gravity so strong it even sucks light in! that's why it's called a 'black' hole.
2006-09-09 00:35:44
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answer #5
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answered by Deek 3
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Hmmm.. Interesting question. As they are related in a way. It started with looking for distance measurements and our quest for the distance to the galactic Centre (Ro). Of course these started as early as 1918 when Shapley made his first estimate (usig the correct method) and has been successively refined since. But it is the methods used that resulted in the detection of the SMBH. The distance calculation to the H2O Masers in Sgr B2 (N) and B2(M) in 1993 [Reid] was followed up a decade later by observations of S2's orbit around Sgr A when the technology became available to see through to the Galactic Center (Radio and IR astronomy) though the motion of Sgr A was first noted and measured in 1986 [Backer] Dark Matter was only postulated when it was found that the orbital rotation of matter in the galaxy did not slow (but remained constant) as distance increased from the galactic core and the mass of what we could see failed to account for the mass that was needed to produce this phenomina (the Missing Mass theory). However it was Fritz Zwicky in 1933 who first came up with the theory after observations made of the coma Cluster of Galaxies. Although BH's were predicted by theory I believe both SMBH and Dark Matter were the result of observations and I think Dark Matter came first.
2016-03-27 03:52:10
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answer #6
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answered by Anonymous
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My opinion? "dark energy","dark matter" and "black holes" are the opposite energy that created the universe. All that darkness is hell itself.
2006-09-09 00:31:51
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answer #7
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answered by ♥ Karen ♥ 4
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The term"DARK ENERGY","DARK HOLES",DARK MATTER",is a scientific name and is mainly associated with the exploration of space and its physical relationship.
2006-09-09 00:44:57
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answer #8
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answered by kezia 1
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black holes r actually not black.......
wen a star dies it sucks all the energy around it also light
its like a supercompresor enrgy condense there
dark matter is i guess anti matter
2006-09-09 00:37:41
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answer #9
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answered by ~MECHIE~ 1
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I don't know who you are, but there is NO way you should be asking these questions. Stick to stuff like; "How do you make hash brownies!"
Allan W Janssen is the author of The Plain Truth About God-101 (what the church doesn't want you to know!) at; www.God-101.com
And the petition to have people mind their own business instead of yours at; http://www.petitiononline.com/moses/petition.html
2006-09-09 04:56:43
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answer #10
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answered by Moses 2
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