
Finding gravitational n-body choreographies - archgoon
http://gminton.org/#choreo
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musgravepeter
Very interesting and a topic I have been very interested in (see e.g. N-Body
on iOS or nbodyphysics.com).

Is there some minimal stability criteria for a curve to considered a
choreography or is it enough that the path is an extrema of the action? Will
e.g. the bodies make even one traversal of the path before going "off into the
wild"?

I'd love a feature to extract positions and velocities for further study.

Awesome site.

~~~
RBerenguel
From my former department:
[http://www.maia.ub.es/dsg/nbody.html](http://www.maia.ub.es/dsg/nbody.html)

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kartikkumar
The 3-body problem never ceases to amaze me. I've had so much fun playing with
choreographies over the last few years, and detecting chaos. Despite the
N-body problem being age-old, there's still so much cutting edge work being
done on figuring out where various patterns and (sub)structures come from. The
Kepler dataset [1] has provided a brilliant starting point to probe a lot of
seemingly insane planet configurations.

One of the most fascinating restricted problems I've worked on is the Sitnikov
problem [2].

[1]
[http://exoplanetarchive.ipac.caltech.edu/docs/KeplerMission....](http://exoplanetarchive.ipac.caltech.edu/docs/KeplerMission.html)

[2]
[http://www.scholarpedia.org/article/Sitnikov_problem](http://www.scholarpedia.org/article/Sitnikov_problem)

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gus_massa
It'd be interesting (but difficult) that the program can recognize the known
choreographies (and rotated versions) and show the data.

It' difficult to find a choreography that is not a circle. I found the circle-
with-hearth choreography and I was very happy until I saw (3-planets, position
(6,1)).

And another feature request. I'd like to link to a choreography, at least to a
well known choreography and perhaps to a user generated choreography.

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da-bacon
Cris Moore and coworkers found a bunch of these
[http://tuvalu.santafe.edu/~moore/gallery.html](http://tuvalu.santafe.edu/~moore/gallery.html)
Including this awesome 28-mass one
[http://tuvalu.santafe.edu/~moore/cubic28.loop.gif](http://tuvalu.santafe.edu/~moore/cubic28.loop.gif)

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rwinn
Very cool! I can't wait until we become a type III civilisation and have
animated constellations to look up at.

It would be interesting to know how fast they need to move and close you would
need to place them to your home planet for the animation to be fast enough so
you can observe a full loop in a couple of minutes.

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raverbashing
It seems to me these choreographies are of theoretical interest, but in
practice it would be hard to get a real choreography like those between
planets

(Especially because of mass differences and the exact speeds they need to form
those)

Which doesn't mean they might not form a different choreography

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tjradcliffe
This is fabulous! I had heard there were figure-8 stable 3-body configurations
but had never modeled one. Just sketch a figure-8 as the starting orbit and
you'll see immediately how it works. Really beautiful work!

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quarterwave
Would the symmetry groups (point groups?) be different for 3D?

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dcgoss
Fantastic, but dangerous for your productivity ;)

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tjradcliffe
Oh yeah. I'd love to see some indication of how stable these configurations
are. A lot of them look pretty wobbly.

