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 Post subject: Welcome and Outlook
PostPosted: Sun, 02-09-07, 10:53 GMT 
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The Cosmological Visualization Project Forum
We hope you will collaborate, contribute, discuss, and share your ideas with us here.

This forum is supposed to represent a preparatory platform for Fridger's ambitious project of scientific visualization beyond our Milky Way, i.e essentially beyond the proper reach of Celestia.

The underlying space-time framework must be radically modified to rest on General Relativity, include the expansion of the Universe, use a proper (comoving) distance definition at cosmological time and length scales, focus on the large scale filiamentary structure of matter, on Dark Matter and weak lensing and many other exciting cosmological visualization aspects at the pioneering research front.

One crucial pilar of approach, is to incorporate a so-called 3D conformal display mode throughout!

"3D conformal kinematics" will make it possible to travel essentially from ones backyard seemlessly to the high redshift frontier, even close to the origin of the cosmic microwave background (CMB) radiation [where the Universe becomes opaque and was only ~400 000 years old!]

The conformal mapping in 2D has only recently been invented and exploited with tremendous success, both in the media and among the science community. Not surprisingly, since it comes from a pretty good address :lol:

http://www.astro.princeton.edu/~mjuric/universe/
http://arxiv.org/abs/astro-ph//0310571 (original paper)

Such a 3D conformal projection of the entire Universe preserves shapes locally. Objects are displayed with sizes that are proportional to the actual (angular) sizes they subtend in the sky.

Yet distances appear squeezed logarithmically!

Crucial progress for our visualization project came recently from the publication of extensive "Mock Catalogs" of large-scale structure "data" that have been achieved with huge amounts of computer resources, based on the N-body simulation algorithm. On the one hand, they perfectly match the real Sloan Digital Sky Survey (SDSS) data, on the other hand they directly reflect the underlying cosmological model and its parameters.

Most importantly for visualization, and unlike the SDSS data, the "mock" data provide a smooth data coverage of a large volume in space-time!

Just watch this and get inspired....
  • The Dark Matter Filiaments in the Universe (640x480, divx5 format, 13.4 MB)

    Caption: "This video shows the DARK MATTER distribution in the Universe at the present time, based on the Millennium Simulation, the largest N-body simulation carried out thus far (more than 10000000000 particles). By zooming in on a massive cluster of galaxies, the movie highlights the morphology of the structure on different scales, and the large dynamic range of the simulation (100000 per dimension in 3D). The zoom extends from scales of several Gpc down to resolved substructures as small as ~10 kpc."

    (If divx5 video is not displayed, please go to
    Fridger's MiniTutorial to find out about the simple remedies! )

    If things eventually work for you, don't miss this one
  • Fast 3D flight through the "Millenium" Universe (1024 x768, divx5, 60 MB )

    Caption: "A 3-dimensional visualization of the Millennium Simulation. The movie shows a journey through the simulated universe. On the way, we visit a rich cluster of galaxies and fly around it. During the two minutes of the movie, we travel a distance for which light would need more than 2.4 billion years."

    When you look at the real data from the Sloan Digital Sky Survey (SDSS), precisely this sort of large-scale filiaments of millions of galaxies are also observed for luminous matter.

Most interestingly physics-wise, one may directly visualize the impact of different geometries i.e. cosmologies of space-time etc. Given these data, there are also very ambitious plans for visualization of directly related cosmological observables, like the power spectrum, etc.

All this will be paired with another longstanding pilar of approach, visualization in variable wave-length bands!

As a senior scientist and expert in theoretical cosmology, Fridger knows about the strongly growing demand for scientifically accurate visualization tools in this pioneering area. He is also aware of the huge fascination this growing field has for the upcoming generation of young scientists ...

So we hope also on YOUR enthusiasm and active help to make this project come to life!

Mona Lisa


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 Post subject:
PostPosted: Sun, 14-10-07, 23:54 GMT 
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Sorry, but I have a question concerning the fast flight video.

What exactly is it supposed to represent? It was pretty, but I have absolutely
NO idea what it displays. Is there an explanation somewhere that I missed?

Thanks, Bob

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 Post subject:
PostPosted: Mon, 15-10-07, 0:36 GMT 
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BobHegwood wrote:
Sorry, but I have a question concerning the fast flight video.

What exactly is it supposed to represent? It was pretty, but I have absolutely
NO idea what it displays. Is there an explanation somewhere that I missed?


It's the way the matter is distributed at very large scale. In a few words, that's how look a tiny piece of the universe. But Fridger will explain better for sure...


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 Post subject:
PostPosted: Fri, 26-10-07, 23:45 GMT 
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Okay, I guess I'll just wait for the book. Sheesh!

I think I understand the underlying principle here, but the imagery doesn't
explain - at least to me - what's happening. Are we looking at matter in
terms of dust particles? asteroids? molecules? atoms? If we can't see dark
matter, how is it deduced from the normal matter that we DO see? As far
as I know, dark matter is a nice simple explanation for scientists to explain
why gravity and galaxies don't work precisely in the way that they thought
they should.

Elucidation please?

Thanks, curious Bob

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 Post subject:
PostPosted: Sat, 27-10-07, 9:48 GMT 
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BobHegwood wrote:
Sorry, but I have a question concerning the fast flight video.

What exactly is it supposed to represent? It was pretty, but I have absolutely
NO idea what it displays. Is there an explanation somewhere that I missed?

Thanks, Bob


Bob,

for that reason MonaLisa had quoted just before the videos a nice summary paper about the Millenium Simulation.

http://www.mpa-garching.mpg.de/galform/millennium/

The two videos are links to that Millenium site and the explanations are also found there:

The first video visualizes the subtle filiaments of DARK MATTER in the Universe from this seminal Millenium Simulation. Their results are in excellent agreement with the actually observed filiamentary structure of galaxies and quasars in the luminous Universe. Each dot you can see in that densely filled volume corresponds to a galaxy or a quasar!

The fast flight video represents

Caption: " a 3-dimensional visualization of the Millennium Simulation. The movie shows a journey through the simulated universe. On the way, we visit a rich cluster of galaxies and fly around it. During the two minutes of the movie, we travel a distance for which light would need more than 2.4 billion years."

When you look at the real data from the Sloan Digital Sky Survey (SDSS), precisely this sort of large-scale filiaments of millions of galaxies are also observed for luminous matter.

After noticing that our embedded video feature does not work anymore on our new Ibiblio host, MonaLisa has reedited the above video links and added the original captions from the Millenium site. I hope this is a bit clearer now.

Bye Fridger

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 Post subject:
PostPosted: Sat, 27-10-07, 13:57 GMT 
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t00fri wrote:

After noticing that our embedded video feature does not work anymore on our new Ibiblio host, MonaLisa has reedited the above video links and added the original captions from the Millenium site. I hope this is a bit clearer now.

Bye Fridger


Better now sir... Thanks for the clarifications. Remember too, that you're
talking to "Brain-Dead" Bob. :wink:

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