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Dark Matter Discovered
sebFlyte writes "Wired is reporting that scientists have come up to a solution as to where all the matter in the universe actually is. Experiments being done with Chandra, NASA's X-ray telescope have shown up a likely candidate for the solution of the dark matter problem. There are massive quantities of Baryons in a super-heated gas cloud several hundred million light years away."
There are massive quantities of Baryons in a super-heated gas gloud several hundred million light years away."
Which, IMHO, is a damn fine place for them to be, rather than here.
The absorption pattern, as detected by Chandra, is consistent with interference caused by carbon, neon, nitrogen and oxygen ions -- in other words, baryons.
It's really a neon sign on Frogstar World B announcing the construction of a restaurant to be constructed on this location in several billion years and reservations are welcome.
"Assuming that what we see is a standard portion of the universe, we extrapolated the data and derived the volume density (of baryons in all the clouds) -- and it's consistent with 50 percent," said astronomer Fabrizio Nicastro, of the Harvard-Smithsonian Center for Astrophysics and lead author of the study.
Later a two-headed, three-armed man entered and ate a piece of fairycake and destroyed their model.
Whereas baryons account for 4 percent of the total matter and energy in the universe, dark matter is thought to make up 23 percent. The remaining 73 percent of the so-called matter-energy budget consists of what scientists call "dark energy." This energy acts like an anti-gravitational force that, in theory, is causing the universe to expand rather than contract.
And here I thought it all existed somewhere along Lucas Valley Road and explained the Jar Jar character and Episodes I-III...
A feeling of having made the same mistake before: Deja Foobar
And would this "superheated gas pocket" perchance reside in Nibbler's lower intestinal tract? ;D
Here's a picture.
Wired is reporting that scientists have come up to a solution as to where all the matter in the universe actually is.
WIRED also said that "Push is the next Big Thing."
The summary is not correct (big surprise there) in that this is a confirmation of a long-suspected theory as to where the missing ordinary (baryonic) matter in the universe is. This does not solve the dark matter problem at all.
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Read more at the press release from the Chandra team at Marshall: http://www.spaceref.com/news/viewpr.html?pid=1604
Dark matter is yet another topic altogether, as is the even more elusive dark energy.
This should be "Missing Matter Discovered" not "Dark Matter Discovered"
They HAVE NOT found dark matter, they've found the 'missing matter' as the article says. They have found a clue as to the dark matter, as a result of the discovery.
Although discovering the dark matter would be much cooler, (yeah I was excited when I read the title).
[rant] Why is it the only 3 times I've 'emailed the on duty editor' before publishing, I've been ignored and the mistakes gone through?? [/rant]
Windows in 6 Bytes (IA-32) : 90 90 90 90 CD 19
In case anyone's wondering what slashdot is...
http://www.slashdot.org/
Can I have my +5 informative now??
Windows in 6 Bytes (IA-32) : 90 90 90 90 CD 19
Tachyons are in fact hypothesized faster-than-light-particles, appearing for instance in certain string theory scenarios.
:-)
But baryons are by no means the counterpart to tachyons. All known elementary particles in the universe are either fermions (particles with spin in integer multiples of 1/2) or bosons (particles with integer spin). Bosons include the photon, the gluon and many others. The fermions are further subdivided into leptons and quarks. Leptons include the electron and the electron neutrino among others. Baryons are particles made up of three quarks, and are fermions and include among others, the proton and neutron, which are the most commonly found baryons in nature, since all heavier baryons normally decay.
Two quarks (fermions) can combine to form mesons, which are in fact bosonic in nature (since two quarks with spin half combine to form a particle with integer spin).
Hope that confused the issue a little
A bit more on-topic: Finding baryons in this amount is a big deal, since baryon has previously been suspected to primarily exist in galaxies, and only in small amounts outside galaxies. While it by no means doesn't solve all problems of cosmology, it is a big help.
> > In case anyone's wondering what a baryon is...
> > http://en.wikipedia.org/wiki/Baryon
> In case anyone's wondering what slashdot is...
> http://www.slashdot.org/
In case anyone's wondering why the hell am I wasting my time so pointlessly.... I have no life.
Assuming that what we see is a standard portion of the universe
An astrophysicist, a physicist, and a mathematician are attending a conference in Scotland. During a break, they take a walk through some of the countryside, and come upon a black sheep.
"Aha," exclaims the astrophysicist. "I had no idea that all sheep in Scotland are black."
The physicist looks at her colleague in disbelief. "All sheep in Scotland are black? Are you nuts? We've only seen one sheep!"
The mathematician interrupts. "And only one side of that sheep."
First, I had to look up "tachyon". You are right, tachyons are apparently particles that travel faster than the speed of light. I've only heard the term from Star Trek, and for the time being that's where these particles are from - the realm of (science) fiction. I've certainly never had them mentioned in class!
Baryons are not the counterpart to tachyons. Baryons are simply particles that are made up of quarks. The two best known examples are neutrons and protons, which make up virtually all of the stuff you own. Yes, baryonic matter is pretty much everything we interact with.
Two examples of particles that are very common and all around us are electrons and neutrinos. You're familiar with electrons (which are not baryons!), and the nuclear reactions in the Sun are constantly producing a mind-boggling number of neutrinos. Generated in the centre, they travel at nearly the speed of light which means that the ones passing through your body right now are about 8 minutes old. By comparison, the light from the Sun (photons, also not baryons) bounces off all the photons there, so by the time it actually reaches you it's about a million years old.
Finally, and most importantly, dark matter has not been discovered. You are also right in that the reporter is very much out of his depth. The article states that there is evidence for baryons to be found in places where we have not seen them before. What's one theory as to how they got there? Dark matter.
Yeah, at least part of them. You can go to my website above, hit "Astronomy Work" link on the left, and be taken to http:physics.uwyo.edu/~mbrother where you'll find links to three recent courses I've taught. The intro astronomy course (1050) is currently in session and so the slides for that one are incomplete. These are slides, meant to accompany lecture, so they aren't enough on their own, but you might enjoy looking anyway.
Professor of Astronomy, Author of Spider Star & Star Dragon (Tor)