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Simulation Explains Supermassive Black Holes
Spy der Mann writes "Using a new computer model of galaxy formation, researchers from Carnegie Mellon University have shown that growing black holes release a blast of energy that fundamentally regulates galaxy evolution and black hole growth itself. According to its creators, 'the model explains for the first time observed phenomena and promises to deliver deeper insights into our understanding of galaxy formation and the role of black holes throughout cosmic history'. Hi res pictures and animations (divX) are also available."
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Have you metaroderated recently?
Here are tons of the most recent research papers on black holes. Definitely an good read for anyone with an interest in physics.
Creative Demolition
Astronomy does pretty well with women, at least compared to other hard sciences. At the undergraduate level, it looks to be close to 50/50. Last year I think we had more female applicants for our summer REU program than males. We're going to admit more women than men into our graduate program this year, too. At the more senior levels, there are fewer women, but the numbers more or less match the historical demographics. My PhD advisor was female, and I have lots of female collaborators and a female grad student. Di Matteo isn't too old -- my generation, 30s. Physics, on the other hand, is still having its problems...
Professor of Astronomy, Author of Spider Star & Star Dragon (Tor)
The high supernova rate resulting from the burst of star formation is likely more of a problem than a central quasar, especially since the star formation can take place outside of the Galactic center. I give my intro astronomy students a problem to computer what the Galactic core would look like if it was a quasar and there was no intervening gas/dust (a really big if, since there is a lot of obscuration now).
Quasars can be 1000 times more luminous than an entire galaxy. The absolute magnitude of such a luminous quasar would be about M = -28.5. If the black hole in the center of our galaxy became a quasar, and obscuring gas and dust did not dim it, what would the apparent magnitude of the galactic core be? Think about the answer and what that would look like in the sky.
The answer is a magnitude of -13.9, about the same as the full moon. It would be more concentrated that the light of the moon, and you'd be able to see it in the day time. But, as I said, intervening gas/dust would diminish it's light, and the Milky Way and Andromeda do not have black holes massive enough to shine as brightly as my example. Our atmosphere would also be there to protect us from X-rays and UV, much as it does now.
Professor of Astronomy, Author of Spider Star & Star Dragon (Tor)
The origin of the X-rays are not well understood, but are thought primarily to come from upscattering of thermal photons in a very hot atmosphere above the accretion disk. All the light basically comes from the stuff right around the black holes moving at relativistic speeds, not the black holes themselves.
Professor of Astronomy, Author of Spider Star & Star Dragon (Tor)