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Possible Dark Matter Signs At the Core
Scientific American has a piece on speculation that dark matter may be behind diffuse radiation in the galactic center. Beginning in 2003, researchers led by Douglas Finkbeiner noticed a curious excess of microwave radiation in the WMAP data, after all known sources of such radiation were accounted for. Data from NASA's Fermi Gamma-Ray Space Telescope resulted in a similar anomaly in gamma rays. "A paper posted to the physics preprint Web site arXiv.org on October 26 and submitted to the Astrophysical Journal points to a possible signature of dark matter in the Milky Way, although the study's authors are careful to keep their observations empirical and table such speculation... In the new paper [the researchers] describe the Fermi gamma-ray haze and make the claim that it confirms the synchrotron origin of the WMAP microwave haze. And as with the microwave haze, the authors argue that the electrons responsible for the gamma-ray haze appear to originate from an unknown astrophysical process. ... 'We are absolutely in the process of exploring the Fermi haze in the context of dark matter physics,' [one of them] says."
Of course it's dark matter in the middle
The difference is that dark matter and dark energy can be tested for in various ways; a deity can't be.
When physicists can't explain something they may use a place holder at times but there's no chance of just giving up like the "god did it" explanation does.
Sigs are too short to say anything truly profound so read the above post instead.
CAPTAIN KIRK: Spock, come in here, can you make sense of these readings?
SPOCK: Captain, it appears that dark matter may be behind diffuse radiation in the galactic center.
CAPTAIN KIRK: It's the most magnificent thing I've ever seen!
SPOCK: It is...fascinating.
CAPTAIN KIRK: But why would diffuse radiation need a starship?
DR. MCCOY: Come on over here, boys! This galactic dick ain't gonna suck itself!
Thanks for reading and supporting fan fiction.
(-1, Raw and Uncut is the only way to read)
Like "gravity", dark matter is the name given to a phenomenon or set of phenomena that appear related, not necessarily an actual thing or force. We don't know what gravity actually "is" under the hood; we only know what it does. Gravity is a model that explains observations nicely. But the actual workings behind it are still elusive. We've yet to successfully break it down into sub-mechanisms or sub-models, like knowing that cars move and the patterns of their movements, but not why they move.
Dark matter may actually be many different forces or causes, and perhaps in the future may be split up or re-assigned to other "forces" (models). At this point in time it's merely a guess that it's all one thing. Gravity may also turn out to be multiple things that only appear to be one in the same from our limited perspective and observations. We have to peel the onion one layer at a time, and may never reach the final center layer (if there is such a thing).
Table-ized A.I.
Can't explain something, Dark Matter is the reason! Can't find a cause, Dark Matter is it!
This is completely incorrect. This work is the result of looking for Dark Matter. Dark Matter is the best explanation for galactic rotation curves and the cosmic microwave background. Depending on what the Dark Matter is it may annihilate with itself and produce, amongst other things, electron-positron pairs. In fact the paper is really a very beautiful and elegant bit of work since the first bit of evidence which lead to this comes from the background 'noise' of one of the major pieces of evidence for Dark Matter - the WMAP data! As such, far from noticing something and then attributing it to Dark Matter, this is actively looking for something that suggests evidence for Dark Matter. True the evidence does not show that it HAS to be Dark Matter but if you cannot attribute it to anything else which is known and you have models which suggest that Dark Matter might produce such a signal it is very interesting.
Arkani-Hamed et al have a model which may explain this and which, if correct, predicts jets of leptons (electrons or muons) at the LHC. This is actually one of the things which my colleagues and I are looking for on the ATLAS Experiment. If we do observe them then this will be further evidence for Dark Matter and not a "oh, something else we cannot explain and put down to Dark Matter". Until we have enough bits of evidence that, combined, show that Dark Matter is the only possible cause there will always be some doubt but that should not be construed as flailing around and using Dark Matter to explain every observation that is inexplicable. Indeed, the fact that we are using Dark Matter models to suggest observations and experiments to perform and then finding that these return "inexplicable" results is very, very interesting!
You're absolutely right. I therefore suggest we call it "Colorless Jesus Powder", in accordance with our new invisible overlord.
I record my sleeptalking
GOD: I am defrosting my dinner.
Simulations of stars in galaxies are approximations because: />3) newton's equations are indeed incorrect however, Einstein's equations only dominate to a significant degree under unusual conditions.
1) there isn't an equation for an exact solution to any gravitationally bound system containing more than 5 objects.
2) stars in a typical galaxy are not uniform so the simulations must take this into account as a best guess. br
In so far as dark matter is concerned, you are incorrect. Experiments like the Cryogenic Dark Matter Search are attempting to detect dark matter particles directly, we've got neutrino detectors looking for evidence of annihilation events... Particle accelerator experiments attempting to actually synthesize dark matter candidates.. To claim that there isn't a way to test the dark matter hypothesis would be grossly inaccurate.
Disclaimer: Physics isn't my major but I did study quite a bit of it in high school and college.
Sigs are too short to say anything truly profound so read the above post instead.
This is more along the lines of "our equations don't explain the observed motion of galaxies, therefore, there's matter there we can't see or touch."
Wow! I never thought they would do things like that! I would have expected things to go like this:
"our equations don't explain the observed motion of galaxies, therefore, it's reasonable to hypothesize that there's matter there we can't see or touch, let's test it."
And then they'd go and look for evidence or something. Thanks for correcting me!
That's just not a logical conclusion. It leaves out the much more likely answer that our understanding of the equations of motion is wrong.
So all that stuff I heard about MOND was just in my head? Thanks for grounding me in reality!
Most galaxy motion simulations are based on either Newtonian mechanics or "modified Newtonian" mechanics, even though both are known to be wrong. Einstein showed them to be wrong over a hundred years ago!
You're right! It's quite likely that thousands and thousands of astrophysicists have spent decades researching a problem that has such an obvious solution. You're a veritable font of wisdom!
I studied physics at University, and both me and a friend of mine noted during our studies that Physics seems to overuse simplified equations ... Those simple equations are the ones we learned about also. They're wrong. In many practical cases, the error can exceed 30%!
O M G ! - W T F ! Low level physics classes use lots of simplifications? That explains why I can't find massless ropes and frictionless pulleys on E-Bay!
Magic?
Persistent Volume manager for Kubernetes - https://github.com/dwimsey/openshift-pvmanager
The difference is that dark matter and dark energy can be tested for in various ways; a deity can't be.
Well, technically you can test for existence of a deity.... you just can't come back to tell the rest of us about it afterwards.