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Simulations Predict Where We Can Find Dark Matter
p1234 writes with this excerpt from the Max Planck Institute for Astrophysics:
"Simulations by the Virgo team show how the Milky Way's halo grew through a series of violent collisions and mergers from millions of much smaller clumps that emerged from the Big Bang. ... If Fermi does detect the predicted emission from the Milky Way's smooth inner halo, then it may, if we are lucky, also see gamma-rays from small (and otherwise invisible) clumps of dark matter which happen to lie particularly close to the Sun. ... The largest simulation took 3.5 million processor hours to complete. Volker Springel was responsible for shepherding the calculation through the machine and said: 'At times I thought it would never finish.' Max Planck Director, Professor Simon White, remarked that 'These calculations finally allow us to see what the dark matter distribution should look like near the Sun where we might stand a chance of detecting it.'"
We discussed a related simulation a few months ago.
"I wonder if dark matter to them is like a Ubuntu release to most of us?"
Maybe, the answer is difficult, it's much like Schroedinger's cat.
until it's observed you cannot tell if it is there or not.
https://www.gnu.org/philosophy/free-sw.html
Don't bother reading the paper. They discovered that they could find dark matter "in space" if it exists.
Did you read the same article I did? Before this simulation their best guess was to look at other galaxies and target their centers. However, the simulation revealed that they have a better chance if they look at our own galaxy, but 10-30 degrees of center, where they should be able to detect gamma rays caused by dark matter.
With the way physics is goign these days, being able to determine that something is in space means you are doing pretty damn good for yourself.
I may agree with what you say, but I will defend to the death your right to face the consequences of saying it.
Sounds like with that many computer hours needed they should set up something similar to Seti@home
It's only paranoia if your wrong...
I find plenty of dark matter when I turn out all the lights prior to going to bed for the evening.
Specifically, I find plenty of dark matter with my toes, which doesn't result in a shout of discovery like, "Eureka!" but ,"*$&#@!"
Due to the proximity to the Sun, the Galactic centre is the brightest and most extended source. This makes it easier to detect than any of the small dark matter subclumps that are distributed over the sky. If one of them should also be detected, it may be devoid of any stars.
I'm interested in that last sentence. Does the gamma radiation push away hydrogen and dust, preventing the formation of stars, or does dark matter exhibit a repulsive gravitational force, clearing a region of space around it? Without referring to Wikipedia, the latter seems unlikely, but the former seems like something we should worry about. How much gamma radiation are we talking about? Should we worry about one of these clumps drifting near the solar system and sterilizing everything? (And if so, how much of an effect would these clumps have on the Drake equation?)
Nothing for 6-digit uids?
Anytime the underlying assumptions of a computer input or algorithm are faulty, even the 3 1/2 million hours of computation on a supercomputer will not lead to the discovery of the scientific truth. The principle of garbage in garbage out still applies. The bottom line is simple: the dark matter emperor is as naked as a newborn.
They have a theory about how dark matter should work. They expended 3.5M hours of computing to make a prediction based on that theory. Now they'll try to confirm the prediction empirically. If the prediction doesn't pan out, the theory will be jettisoned or patched. If the empirical observations agree with the prediction, the theory is left standing until such time as new evidence shows it to be squidgy around the edges. That's how science works.