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Todd Suomela

Sloan Survey Expands to Explore Larger Universe in 3D - 0 views

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    And though we may be away from those holographic representations, the Sloan Digital Sky Survey will soon be entering its third phase, in an attempt to create the biggest 3D map of the universe created so far.
Todd Suomela

[0806.0377] A Hemispherical Power Asymmetry from Inflation - 0 views

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    Measurements of temperature fluctuations by the Wilkinson Microwave Anisotropy Probe (WMAP) indicate that the fluctuation amplitude in one half of the sky differs from the amplitude in the other half. We show that such an asymmetry cannot be generated during single-field slow-roll inflation without violating constraints to the homogeneity of the Universe. In contrast, a multi-field inflationary theory, the curvaton model, can produce this power asymmetry without violating the homogeneity constraint. The mechanism requires the introduction of a large-amplitude superhorizon perturbation to the curvaton field, possibly a pre-inflationary remnant or a superhorizon curvaton-web structure. The model makes several predictions, including non-Gaussianity and modifications to the inflationary consistency relation, that will be tested with forthcoming CMB experiments.
Todd Suomela

Press Release: Two of the Milky Way's Spiral Arms Go Missing - 0 views

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    Now, new images from NASA's Spitzer Space Telescope are shedding light on the true structure of the Milky Way, revealing that it has just two major arms of stars instead of the four it was previously thought to possess.
Todd Suomela

SAO/NASA ADS: ADS Home Page - 0 views

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    The SAO/NASA Astrophysics Data System (ADS) is a Digital Library portal for researchers in Astronomy and Physics, operated by the Smithsonian Astrophysical Observatory (SAO) under a NASA grant. The ADS maintains three bibliographic databases containing more than 6.9 million records: Astronomy and Astrophysics, Physics, and arXiv e-prints. The main body of data in the ADS consists of bibliographic records, which are searchable through highly customizable query forms, and full-text scans of much of the astronomical literature which can be browsed or searched via our full-text search interface. Integrated in its databases, the ADS provides access and pointers to a wealth of external resources, including electronic articles, data catalogs and archives. We currently have links to over 7.6 million records maintained by our collaborators.
Todd Suomela

Astronomer's Bazaar - 0 views

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    The CDS Service for astronomical Catalogues
Todd Suomela

Astronomical Data Center Home page - 0 views

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    For 25 years, the ADC was a key center for published astronomy data, catalogs, and journal tables. The ADC made these data sets computer readable and developed new methods, tools, and techniques for their preparation and use.
Todd Suomela

Guest Post: Tom Levenson on Isaac Newton as the First Cosmologist | Cosmic Variance - 0 views

  • To make his ambitions absolutely clear Newton used the same phrase for the title of book three. There his readers would discover “The System of the World.” This is where the literary structure of the work really comes into play, in my view. Through book three, Newton takes his audience through a carefully constructed tour of all the places within the grasp of his new physics. It begins with an analysis of the moons of Jupiter, demonstrating that inverse square relationships govern those motions. He went on, to show how the interaction between Jupiter and Saturn would pull each out of a perfect elliptical orbit; the real world, he says here, is messier than a geometer’s dream.
  • Newton knew what he had done. He was no accidental writer. A parabola, of course, is a curve that keeps on going – and that meant that at the end of a very long and very dense book, he lifted off again from the hard ground of daily reality and said, in effect, look: All this math and all these physical ideas govern everything we can see, out to and past the point where we can’t see anymore. Most important, he did so with implacable rigor, a demonstration that, he argued, should leave no room for dissent. He wrote “The theory that corresponds exactly to so nonuniform a motion through the greatest part of the heavens, and that observes the same laws as the theory of the planets and that agrees exactly with exact astronomical observations cannot fail to be true.” (Italics added).
Todd Suomela

Does Time Run Backward in Other Universes?: Scientific American - 1 views

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    The basic laws of physics work equally well forward or backward in time, yet we perceive time to move in one direction only-toward the future. Why?
Todd Suomela

Phoenix Mars Mission - Home - 0 views

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    The University of Arizona is honored to be the first public university to lead a mission to Mars. The Phoenix Mars Mission, scheduled to land May 25, 2008, is the first in NASA's "Scout Program." Scouts are designed to be highly innovative and relatively low-cost complements to major missions being planned as part of the agency's Mars Exploration Program.
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