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Elusive Dark Matter May Be Detected With GPS Satellites
An anonymous reader writes: Two researchers say time disparities identified through the network of satellites that make up our modern GPS infrastructure can help detect dark matter. In a paper in the online version of the scientific journal Nature Physics, they write that dark matter may be organized as a large gas-like collection of topological defects, or energy cracks. "We propose to detect the defects, the dark matter, as they sweep through us with a network of sensitive atomic clocks. The idea is, where the clocks go out of synchronization, we would know that dark matter, the topological defect, has passed by."
Another reader adds this article about research into dark energy:
The particles of the standard model, some type of dark matter and dark energy, and the four fundamental forces. That's all there is, right? But that might not be the case at all. Dark energy may not simply be the energy inherent to space itself, but rather a dynamical property that emerges from the Universe: a sort of fifth force. This is speculation that's been around for over a decade, but there hasn't been a way to test it until now. If this is the case, it may be accessible and testable by simply using presently existing vacuum chamber technology
more like the god damned particle...
my non-physicist brain wants to stuff dark matter into the role of 'barely detectable multiverse'.
I find stuff like this online and find myself wondering if it is all hooey
http://www.math.columbia.edu/~...
How long until we can start to describe the pieces and parts of adjacent universes?
Wherever You Go, There You Are
But I've been accused of worse.
Happiness in intelligent people is the rarest thing I know.
Ernest Hemingway
There is ample observational evidence of dark matter in the form of its gravitational effects. We just don't know what it is. It could be 'ordinary' baryonic matter or something entirely new. It isn't a matter of faith. Pun intended.
I don't care about your history or my karma, I have taken your OP at face value. - No "we" don't need (blind) faith, your self-confessed need for it is merely a consequence of your lackluster search for evidence.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
It can't be "ordinary baryonic matter": we know it doesn't interact with photons even at extreme energy densities, and we also know it doesn't move at or near the speed of light. Both are clear from the CMBR data.
Socialism: a lie told by totalitarians and believed by fools.
iif you'd been born with the courage to post merely pseudo-anonymously
I don't have an account because I don't want or need one.
Nope, the reason is because you can't think of a funky pseudonym. Even if you could you're not allowed to be here except as an AC because you are an asshole!
Does that make me a coward ?
No, but it does make you a dick.
Only in the mind of a fool like you.
Who's more the fool, the fool or the fool who follows the fool. It's a legitimate question from obi wan considering you admit to actually 'choosing' to be an anonymous coward on slashdot. So don't whine because a legitimate user of the site calls you out for what you are. We've sustained your right to anonymous free speech and you used it to prove you are a dick. Way to go, dick, such a mammoth contribution that in years people will read your comments and say to themselves:
What a dick.
Btw I do have an account but a privilege of having an account means I can troll you back as an AC and protect myself because you're an idiot and likely to anonymously troll my posts with your fecal rambling.
Some ACs are ok but Anonymous Coward such as yourself are the parasites on our community that spawn the reason for Beta, go back to reddit or facefuck. Fortunately we can all ignore you simply by turning the moderation selector up until your pathetic, whiney, child like voice can no longer be heard over the boring mundane and somewhat stupid comments that most people skip. I might do that so that I don't see your reply and forget you, meanwhile you will carry the scars of this encounter culminating in rage that builds up inside you until you do something that lands you in the Darwin awards.
Your story will be posted to slashdot and we will all say "what a dick that guys was".
So carry on being an asshole, it's why you don't have an account and no one cares what you are saying anyway.
tt can be baryonic matter, if it is encapsulated in some fashion. I believe your two conditions refer to BBN (not a particularly extreme energy density, BTW) and the Lyman Alpha constraints on Warm Dark Matter (which means it had to drop out of the radiation fluid v ~ c / sqrt(3) pretty early).
Both of these are fulfilled by, e.g., quark nugget dark matter (these would form well before BBN and drop out of the radiation fluid well before needed to fulfill the WDM constraints), as maybe also the recently proposed "macros".
can be baryonic matter, if it is encapsulated in some fashion.
In which case it would hardly qualify as ordinary baryonic matter...
No, it is very different from the ether. The ether was the proposed medium which light propagated through. As such it was a continuous field not clumps of particles. Also the ether was massless and had no gravitational field. Dark Matter has a mass and causes a gravitational field which is how we know that it exists.
No, the reason the Higgs is called the god particle is because you can't have Mass without it.
The fundamental problem with the "standard model" is that it's based on gravity.
Actually the one thing that the Standard Model is absolutely NOT based on is gravity. Gravity being so weak and have an long range actually is responsible for the structures at the largest scales of the Universe which is precisely where we see Dark Matter. The reason for this is that EM is so much stronger that it will force charge cancellation to a large high degree on smaller distance scales: if there is a charge imbalance opposite charges will be rapidly dragged in to create a balance. This cancels EM out at larger distance scales since the charges balance leaving only gravity (the strong and weak nuclear forces being short range [~nucleus] due to their physics).
"Quark nuggets" are ordinary?
Well, I guess that would be technically correct (the best kind of correct!) if true, since 85% of matter is whatever dark matter is. Our matter is the weird stuff.
Socialism: a lie told by totalitarians and believed by fools.
Don't we have to have faith that the scientists aren't cherry-picking chunks of data that give them (almost) the significance they want?
Remember Feynman, in "Cargo Cult Science", describing how experimenters replicating Millikan's famous experiment found ways to fudge their data to match his flawed results? Didn't they have faith he was right?
If y'all don't mind, 4Chan is downstairs.
Faster! Faster! Faster would be better!
Satellites? Okay, here's one for you. The Voyager spacecraft. It traveled outside the solar system and the only minute unpredictable change in vector was due to heat radiating infrared photons from its metal. The measurements were THAT sensitive! And it interacted with exactly zero dark matter. You think some GPS satellite orbiting Earth is going to come up with different results?
Unless the universe has a modest net charge. You'd get localized charge cancellation, but even the slightest charge imbalance would have profound effects on an interstellar scale. Even a charge imbalance far too small to detect in any ordinary, solar system contained instrumentation would have enormous effects in the long-term history of the universe.
It is something to think about.
CERN said the evidence is five sigma or so for a particle more or less where the Higgs was expected (or perhaps about halfway between where two competing theories expected it), but some now doubt whether the particle CERN found is actually the Higgs. See this recent reassessment: http://sdu.dk/en/Om_SDU/Fakult...
This is not a good description. I've no idea what a topological defect or energy crack is.
any net charge would be trivially detectable to have any effect on the interstellar scale. Run the numbers for gods sake.
If information wants to be free, why does my internet connection cost so much?
Yes, they used faith rather than science, even though they were supposed to be conducting scientific experiments. Just because they were doing it wrong doesn't mean that you can extrapolate that to people who do it right.
You're a temporary arrangement of matter sliding towards oblivion in a cold, uncaring universe
I think the issue with the description of "ordinary baryonic matter" is that it was using "ordinary" and "baryonic" synonyms. Not to say (ordinary(baryonic matter)), but (ordinary baryonic(matter)), because "baryonic" is "ordinary", generally speaking.
Ok, here's one for you - Voyager is a cheap ass grade school optical microscope. The GPS constellation is a scanning tunneling microscope. Which would you choose to look at atomic level features?
Seriously, you're comparing apples to the thing least like apples that you can imagine. For starters they're looking at different effects, Voyager's effects manifested as variations in trajectory, while they're looking for variations in (some extremely precise) clocks with the GPS constellation. Voyager is a single bird, while the GPS constellation is an array of 32 birds - which means you have enough that the effects are amenable to statistical analysis. Etc... etc...
I know that but I guess the joke was lost on you.