Milky Way From Paranal
This photo was taken July 21 from Paranal mountain in Chile, home of the Very Large Telescope. The two bright objects at the centre are Antares and Jupiter (right). Alpha Centauri is visible at middle left. The laser from Unit Telescope 4 is aimed at the galactic centre. Astronomers were using the SINFONI instrument to study the massive Black Hole at our galaxy's core. The laser is an aid to adaptive optics. Just last week X-ray astronomers announced a new class of hidden Active Galactic Nuclei (AGN). Every galaxy yet found contains at its centre a massive Black Hole.
Gregory Benford is a physicist and a fine science fiction author. Benford and Raymond Protheroe of University of Adelaide have proposed that Ultra-High Energy Cosmic Rays are the result of ancient AGN's. They suggest that even after an AGN fades from view, the invisible magnetic field could remain. Powerful cosmic rays, whose source has been a mystery, could be the result of these fields. Apparently empty Space could be filled with powerful magnetic fields.
The Big Bang created countless billions of singularities from quantum fluctuations. Once it was thought that all primordial Black Holes were tiny. Size of a PBH is limited by a "horizon distance" that light could have travelled. Since the speed of light near the Big Bang was much higher, singularities could have formed in almost any size. Black Holes formed the seeds of clusters, galaxies and even smaller structures. Stars like Antares and giant planets like Jupiter could be markers for Black Holes. Their products are truly beautiful to behold.
Labels: astronomy, black holes, galaxies
6 Comments:
If all the universe was tiny,isn't that mean that a black holes were tiny too?
You actually saying that black holes expanded with the universe?
Very lovely.
I like your ideas about PBHs and wish I were educated enough to understand the math behind them.
For Alex: At one time the Universe and everything in it were tiny. Quantum uncertainty made some bits more dense than others. These fluctuations expanded rapidly with the Universe. The most dense collapsed into Black Holes. BH's are probably the oldest form of mass in the Universe.
For Eric: This blog will try to keep things non-mathematical when possible. Nice that you are enjoying the postings.
But when the universe expanded,it became less dense than it was in beginning.Nevertheless black holes are continue to exist?
beautiful photo.
have you read any of Benford's sci-fi? he wrote an excellent series of books, "Great Sky River" etc. that ends up in the galactic center
My favourite Benford is TIMESCAPE, about discovery of a way to send messages back in time. The physicist isn't believed at first. In the epilogue he is awarded a Nobel Prize for his less controversial work, like Einstein and the photoelectric effect.
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