Posted on 06/05/2013 2:51:39 PM PDT by LibWhacker
The three-dimensional structure of the local universe may one day become as familiar as our local geography thanks to a new generation of maps that reveal our neighbourhood’s rich complexity and our place within it
The geography of our world is one of the great cultural invariants. There can hardly be the person on the planet who isn’t familiar with the shape of the continents and how they dovetail together or of the Earth is a pale blue sphere orbiting the Sun with seven other planets.
Given a three-dimensional model of the solar system, almost everyone can zoom in from beyond the Oort cloud to the planet Earth and then even further to the street where they live. It is powerful shared knowledge.
But at greater distances, our geographical knowledge becomes a little blurred. Many people will have seen the extraordinary three-dimensional models of the filamentary structures that galaxies form on the larger scales in our universe.
And yet these structures remain strangely unfamiliar. Given an unlabelled three-dimensional model of this large-scale structure of the universe, who could point to the place we call home?
All that should begin to change in the next few years with the increasingly accurate maps that cosmologists are compiling of the three-dimensional distribution of galaxies within universe.
Today, Helene Courtois at the University of Lyon in France and a few buddies show off this newfound knowledge in a movie (and accompanying paper) that they’ve created to explore the rich structure of our galactic neighbourhood.
One of the key questions that this data can help to answer is whether the distribution of visible mass in the universe is an accurate reflection of the distribution of dark matter. Courtois and co so that the data shows that this is indeed the case.
The film does a fine job of showing the three-dimensional structure of this space. It also reveals the limitations of human language in describing this complex tapestry. That’s not really surprising given that our vocabulary has evolved to describe a geography that is essentially two-dimensional.
Just how to describe our position within the three-dimensional filamentary structure of the universe is a challenge that astronomers will have to wrestle with in the coming years.
And since this presents a rather different challenge than ordinary geography, researchers have coined a new term to describe this kind of intergalactic mapping–cosmography.
We can expect to see more of these kinds of 3D maps of the universe as the data becomes better and more easily accessible. And as cosmography grows into a science in its own right. Perhaps one day they will appear as familiar to us as the shape of the continents on this pale blue dot.
Ref: arxiv.org/abs/1306.0091: Cosmography Of The Local Universe
Wow, the narrator’s accent is just too much for me to understand.
Thank goodness, now I will always know where I am.
ping.
Oh, yeah, “local universe.” To make readers think that the astronomers know what’s outside of it.
DUDE LETS GO TO THE ZONE OF AVOIDANCE!
Isn't it 57 planets?
Size is mindboggling.
Oh, but we do know what is outside of the local universe. Astronomers have been studying it for decades. Remember, by “local universe” they don’t mean our universe in some giant multiverse of universes. They only mean our tiny corner of this universe, the one we have known and loved for nearly a century.
Thanks. So what’s outside of the greater universe then?
“DUDE LETS GO TO THE ZONE OF AVOIDANCE!”
Chicago?
I’m just an interested layman, definitely not an expert, but before someone came up with the idea of a multiverse (which is still quite controversial), I think most astronomers and physicists would’ve said there’s is nothing outside of our universe. Our universe is all there is, and it’s expanding. It’s not expanding into something that’s “outside” of it, like a cake in an oven, rather it’s expanding in the sense that new space is being created all the time that wasn’t there before.
Dude...for a layman, that’s a pretty deep concept. Well done.
Where’s the little arrow that says “You Are Here”, I can’t find the route to the food court...
Thanks, very kind of you. I owe that particular interpretation (to the extent I got it correct) to Freeper ‘Physicist,’ who doesn’t come around anymore, much to our detriment.
Don’t go to the cosmic food court. I think we might be on the menu. ;-)
And wash us down with Pangalacticgargleblasters?
Things sure have changed out there since the last time I was abducted.
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