Dark matter/Dark Energy


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Profile Chris SProject donor
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Message 1487926 - Posted: 12 Mar 2014, 18:33:38 UTC

Sorry guys, doesn't cut it with me ....

A thin disk of dark matter running through the Galaxy might be behind the large meteorite strikes that are thought to be responsible for some of Earth’s mass extinctions, including that of the dinosaurs, two theoretical physicists have proposed.

The model is based on a hypothetical form of dark matter described by the authors and their collaborators last year as a means to solve a separate cosmic conundrum. The existence of such a 'dark disk' could be tested soon by astronomical observations.


So many maybes and possibles there, just another scientific paper ....

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Message 1487982 - Posted: 12 Mar 2014, 20:03:51 UTC - in response to Message 1487926.

Sorry guys, doesn't cut it with me ....

A thin disk of dark matter running through the Galaxy might be behind the large meteorite strikes that are thought to be responsible for some of Earth’s mass extinctions, including that of the dinosaurs, two theoretical physicists have proposed.

The model is based on a hypothetical form of dark matter described by the authors and their collaborators last year as a means to solve a separate cosmic conundrum. The existence of such a 'dark disk' could be tested soon by astronomical observations.


So many maybes and possibles there, just another scientific paper ....



Assuming is the only thing we can do on a subject like that...
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Message 1488422 - Posted: 13 Mar 2014, 17:10:59 UTC - in response to Message 1487926.

Hypotheses non fingo (Isaac Newton)
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Message 1488501 - Posted: 13 Mar 2014, 18:54:54 UTC

Some hypotheses can be true but non of them are refuted yet, that's why they're called hypotheses I presume:))
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Message 1488553 - Posted: 13 Mar 2014, 19:49:50 UTC

The more assumptions that are made the less likely a hypothesis becomes. Dark matter and dark energy could be the result of bad interpretations of the observed data and/or incomplete data leading to false conclusions.
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Message 1498938 - Posted: 3 Apr 2014, 4:18:15 UTC
Last modified: 3 Apr 2014, 4:30:13 UTC

https://scontent-a.xx.fbcdn.net/hphotos-frc3/t1.0-9/10002913_10202607101072166_707896720_n.jpg

Just Copy and paste the above URL onto a browser page.

Now why did all the posts change to HTML. Not everyone knows how to post in HTML.

This is not really a work smart not hard way of doing things. It just takes that much longer to place photos and show representations of thoughts theories and ideas.

this could explain what we call dark matter or dark energy. Not just explaining gravity in on downward direction like we do on earth but explaining it in all directions. This would be similar as how we interpret time on earth being far different then how time is interpreted in Space.
If you look at the graphical representation incorporating only two directions combined you can see points that converge more densely. These would be points of very strong gravitational waves creating boundaries and sentry points that keep for example our planet in its delicate balance. Look at the very outer quadrants and you could see a halo of dense gravitational waves being formed. This would mean that in a 3 dimensional sense there would be a outer sphere of dense gravitational waves surrounding the planet at a very large distance from us. maybe containing the moon within that field. How can we measure this to see if it really exists? We have satellites in space that can measure gravitational waves to see if they exist. Maybe that will prove it. This is just my theory. I believe it can be proven mathematically as well. another way to maybe measure the existence is to track a meteor or a comet that enters close to the earth and see if at any point it accelerates, then note the distance of the occurrence, and measure other objects for consistency. This would take a very long time to do, but it would prove the theory. I would believe that at points where gravitational waves are stronger. objects traversing those points would develop acceleration. This could also explain why some accounts of UFO indicate the craft making 90 degree sharp turns and then accelerating rapidly at blinding speed straight up out of the earths atmosphere. They could be manipulating gravitational waves as a propulsion mechanism.
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Message 1499062 - Posted: 3 Apr 2014, 11:43:29 UTC - in response to Message 1498938.
Last modified: 3 Apr 2014, 11:45:47 UTC

https://scontent-a.xx.fbcdn.net/hphotos-frc3/t1.0-9/10002913_10202607101072166_707896720_n.jpg

Just Copy and paste the above URL onto a browser page.

Now why did all the posts change to HTML. Not everyone knows how to post in HTML.

This is not really a work smart not hard way of doing things. It just takes that much longer to place photos and show representations of thoughts theories and ideas.


The forums have never used HTML; they've always used BBCode. I couldn't get your image to display in the post, so I made it 'clickable'.

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Message 1499899 - Posted: 4 Apr 2014, 22:20:57 UTC - in response to Message 1499062.

A new study of gamma-ray light from the center of our galaxy makes the strongest case to date that some of this emission may arise from dark matter, an unknown substance making up most of the material universe. Using publicly available data from NASA's Fermi Gamma-ray Space Telescope, independent scientists at the Fermi National Accelerator Laboratory (Fermilab), the Harvard-Smithsonian Center for Astrophysics (CfA), the Massachusetts Institute of Technology (MIT) and the University of Chicago have developed new maps showing that the galactic center produces more high-energy gamma rays than can be explained by known sources and that this excess emission is consistent with some forms of dark matter.

http://www.nasa.gov/content/goddard/fermi-data-tantalize-with-new-clues-to-dark-matter/index.html

video with link.
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Message 1510045 - Posted: 29 Apr 2014, 21:43:58 UTC - in response to Message 1499899.

dark matter holds galaxies together...??


http://www.huffingtonpost.com/2014/04/29/dark-matter-asteroids-earth_n_5231829.html
Dark Matter Could Send Asteroids Crashing Into Earth, Scientists Say

Dark matter could sling lethal meteors at Earth, potentially causing mass extinctions like the cataclysm that ended the Age of Dinosaurs, Harvard scientists say.
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Message 1510056 - Posted: 29 Apr 2014, 22:03:25 UTC - in response to Message 1510045.
Last modified: 29 Apr 2014, 22:03:43 UTC

dark matter holds galaxies together...??


http://www.huffingtonpost.com/2014/04/29/dark-matter-asteroids-earth_n_5231829.html
Dark Matter Could Send Asteroids Crashing Into Earth, Scientists Say

Dark matter could sling lethal meteors at Earth, potentially causing mass extinctions like the cataclysm that ended the Age of Dinosaurs, Harvard scientists say.



Hmmm... well... most interesting! Thank you Lynn... for those... well... potentially dark tidings :)

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Message 1510152 - Posted: 30 Apr 2014, 4:39:05 UTC

It seems that ultracold neutrons feel only gravity, not dark energy or dark matter.
Phys.Rev.Lett.
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Message 1510237 - Posted: 30 Apr 2014, 9:48:30 UTC
Last modified: 30 Apr 2014, 9:54:13 UTC

The intergalactic medium unveiled


Astronomers have taken unprecedented images of the intergalactic medium -- the diffuse gas that connects galaxies throughout the universe -- with the Cosmic Web Imager. Until now, the structure of the IGM has mostly been a matter for theoretical speculation. However, with observations from the Cosmic Web Imager, deployed on the Hale 200-inch telescope at Palomar Observatory, astronomers are obtaining our first three-dimensional pictures of the IGM.


Though you might not think so on a bright sunny day or even a starlit night, fully 96 percent of the mass and energy in the universe is dark energy and dark matter (first inferred by Caltech's Fritz Zwicky in the 1930s), whose existence we know of only due to its effects on the remaining 4 percent that we can see: normal matter. Of this 4 percent that is normal matter, only one-quarter is made up of stars and galaxies, the bright objects that light our night sky. The remainder, which amounts to only about 3 percent of everything in the universe, is the IGM.

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Message 1511057 - Posted: 2 May 2014, 1:44:55 UTC - in response to Message 1510237.

this is new..

Dark matter, the invisible and mysterious stuff that makes up most of the material universe, might be hiding itself in microscopic black holes, says a team of Russian astrophysicists.

http://www.huffingtonpost.com/2014/05/01/dark-matter-black-holes_n_5246091.html
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Message 1511120 - Posted: 2 May 2014, 6:32:59 UTC

I don't really have any theory about dark matter. Most people say that it is the stuff that glues the universe together, else the stars would fly about all over the place. But all stars are part of galaxies, and at the centre of each Galaxy is believed to be a super massive black hole. It is the intense gravity exerted by that that which holds galaxies together. Our own one is Saggitarius A.

But if they say that "something" called dark matter needs to exist, to explain what we observe then that is fine with me. Doesn't alter my view of anything else.

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Message 1511193 - Posted: 2 May 2014, 9:40:56 UTC

the stuff that glues the universe together


Dark matter glues galaxies together. Dark energy otoh repulses everything and makes the Universe expand in a faster and faster rate...
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Message 1511197 - Posted: 2 May 2014, 9:51:38 UTC

It's all interesting stuff

Theorists still don't know what the correct explanation is, but they have given the solution a name. It is called dark energy.

Universe = 68% dark energy, ~27% dark matter, ~5% normal matter.

We are much more certain what dark matter is not, than we are what it is.

NASA

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Message 1511237 - Posted: 2 May 2014, 12:15:33 UTC

Having produced neutrons in my youth I believe in their existence. They don't feel any dark energy or dark matter attraction.
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Message 1511251 - Posted: 2 May 2014, 13:32:44 UTC

Dark matter doesn't interact with normal matter, that's one of the reasons it is so hard to trace.

We do have the hypothetical particles, called WIMPS (weakly interacting massive particles) They interact through the weak nuclear force and gravitation; Because they do not interact through electromagnetism they cannot be seen directly, and because they do not interact through the strong nuclear force they do not interact strongly with atomic nuclei. Because of this they don't interact with normal particles, but do interact with other WIMPs. Also, this combination of properties gives WIMPs many of the properties of neutrinos, except for being far more massive and therefore slower. When WIMPs react with each other they emit gamma rays.

Found an interesting read on the interactions between dark energy and dark matter:



https://www.imprs-astro.mpg.de/sites/default/files/Baldi_Marco_2009_0.pdf
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Message 1511298 - Posted: 2 May 2014, 14:51:53 UTC - in response to Message 1511120.

I don't really have any theory about dark matter. Most people say that it is the stuff that glues the universe together, else the stars would fly about all over the place. But all stars are part of galaxies, and at the centre of each Galaxy is believed to be a super massive black hole. It is the intense gravity exerted by that that which holds galaxies together. Our own one is Saggitarius A.

But if they say that "something" called dark matter needs to exist, to explain what we observe then that is fine with me. Doesn't alter my view of anything else.

According to the experts, the black holes at the center of galaxies don't have enough mass on their own to hold a galaxy together. Since I am not educated enough in these things I have grown to accept the analysis of the experts, but I am sure that before too long a greater understanding will reveal that even the current theories are incomplete and flawed.
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Message 1511311 - Posted: 2 May 2014, 15:10:02 UTC

So far LHC has not found any neutralino or other WIMP. They must be more massive than the Higgs boson and may be found when LHC is upgraded to 14 TeV or must wait for the SuperLHC with a circumference of 100 km. I believe in experiments more than in theory.
Tullio
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