Simulations Predict Where We Can Find Dark Matter 61
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.
Re:Hope it works out for you (Score:1, Insightful)
places devoid of any stars (Score:4, Insightful)
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?)