the cosmic simulator daniel kasen (ucb & lbnl) peter nugent, rollin thomas, julian borrill &...
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The Cosmic The Cosmic SimulatorSimulator
Daniel Kasen (UCB & LBNL)Daniel Kasen (UCB & LBNL)
Peter Nugent, Rollin Thomas, Peter Nugent, Rollin Thomas,
Julian Borrill & Christina Siegerist Julian Borrill & Christina Siegerist
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The History of the The History of the UniverseUniverse
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Foundations for a Cosmic Foundations for a Cosmic SimulatorSimulator
Planck
Sloan
LISA
JWST
EarlyUniverse
Galaxies & Large Scale Structure
Star Formation
Supernovae
Black Holes
JDEM
Observations
Simulations
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The National Virtual The National Virtual Observatory Observatory (NVO)(NVO)
The NVO links together disparate observational programs by:
- connecting distributed data components
- linking them to Grid computing resources
- developing standards for data interchange and data provenance
Computational Astrophysics must be linked in a similar fashion, and soon, or the data will overtake us….
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Cosmic SimulatorCosmic SimulatorSimulations no longer exist in splendid isolation, but now overlap in the intermediate regimes between their core domains. Component simulations can be linked together to provide a coherent, end-to-end, history of the Cosmos.
Simulation data will be made accessible for comparison with observations and for providing the initial conditions for the next simulation step.
Key issues include computational steering, grid and sub-grid selection and interpolation, and data interfaces.
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The Early UniverseThe Early Universe
Observations:Planck/CMB
Simulations:Julian Borrill
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Galaxy/Structure Galaxy/Structure FormationFormation
Observations:Sloan Digital Sky
Survey (SDSS)
Simulations:Joel Primack
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Supernova ExplosionsSupernova Explosions
Observations:Joint Dark EnergyMission (JDEM)
Simulations:A.Mezzacappa,
P. Nugent, D. Kasen
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Black Holes and Gravitational Black Holes and Gravitational RadiationRadiation
Observations:Laser Interferometer
from Space (LISA)
Simulations:Ed Siedel
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The Orgin of SupernovaeThe Orgin of SupernovaeConfronting Theory and Confronting Theory and
ObservationsObservations
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SNe Ia and their SNe Ia and their CompanionsCompanions
courtesy: http://zenith.as.arizona.edu/~burrows/movies.html
Marietta et al. (2000) examined the effects of asupernova running into its companion star.
The impact carves out a holein the supernova...
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Supernovae With a Hole?Supernovae With a Hole?
Unfortunately observed supernovae are too far away to be resolved, so we can’t directly look for such a hole.
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Supernova Spectra Supernova Spectra with simulations, we can interpret the with simulations, we can interpret the
colorscolors
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3-D Monte Carlo Radiation 3-D Monte Carlo Radiation TransferTransfer
Memory/Computing:Memory/Computing:
~ 10~ 1066 cells/10 cells/1033 wavelengths wavelengths
~20 GB~20 GB
~10^11 photons: ~10^11 photons:
~20,000 hours~20,000 hours
Scales well, currently runsScales well, currently runs
on ~2056 processors onon ~2056 processors on
the IBM SP Seaborg at the IBM SP Seaborg at NERSCNERSC
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Looking down and Looking down and around around the holethe hole
QuickTime™ and aNone decompressor
are needed to see this picture.
Changes in the spectrum provide signatures of the hole
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Diversity and AsymmetryDiversity and AsymmetryA unifying picture?A unifying picture?
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ConclusionsConclusionsAstronomy faces a data avalanche. Breakthroughs and advancements in telescope, detector, and computer technology allow astronomical surveys to produce terabytes of images and catalogs. These datasets will cover large fractions of the sky spanning the spectrum from gamma-rays through optical to radio, and will allow us to probe fundamental questions in physics and astronomy that were unimaginable just a few years ago.
However, the study and analysis of this data can only be accomplished with equal advancements in computational simulations and data reduction. The National Academy of Science Astronomy and Astrophysics Survey Committee in its Decadal survey recommends a multi-agency effort to establish the National Virtual Observatory (NVO).
Given the increasing involvement of the DOE in astrophysics and its long history of excellence in computational research the Cosmic Simulator is a natural goal. It also provides a direct link to the NVO. Together these will provide both the framework to link the archival data sets, ongoing space and ground surveys, and computational resources necessary to produce the best science possible as we attempt to understand the Universe from beginning to end.