Less violent as opposed to alternative :-)
I had sort of danced around the issue because to be honest I thought that preearth might actually do some research rather than dribble on.
Since you have interest Bill S I will give you some background.
What he is setting up is an called an "astrometric binary" planets.
Here is a quick overview for it
http://csep10.phys.utk.edu/astr162/lect/binaries/astrometric.htmlThe orbital mechanics behind binaries are somewhat demanding we have been studying them in the Kuiper belt ... some light reading
(http://www.gps.caltech.edu/~mbrown/out/kbbook/Chapters/Noll_Binaries.pdf)
Pluto/Charon which is sort of what he is looking at with preearth/heaven (http://lasp.colorado.edu/~bagenal/1010/SESSIONS/17.PlutoCharon.html)
You notice charon most likely doesn't have an atmosphere as with most of these systems because two atmospheres on each planet means tides on each system and that really makes things well interesting :-)
Now preearths problem is he needs to bring the binaries in and in slowly so they meet.
As I discussed above there is a further complication to all this so lets bring it in the earths axis tilt of (22-24 degree). What you really have is (
http://faculty.ifmo.ru/butikov/Applets/Precession.html) set the prolateness to near 1.0 for sphere.
The earth has a forward tilt that means heaven would have had to be a retrograde twin if we want counter rotation (
http://en.wikipedia.org/wiki/Retrograde_orbit).
This is also good because it gives the effect he wants which due to tidal deceleration, bodies in retrograde orbit will slow down and eventually impact the central body.
My problem is he wants the bodies somewhat similar in size and we have both effects needed at once astrometric twin and retorgrade. The tilts will be all wrong I suspect you will still get a big smash. A lighter faster heaven I suspect would make the situation easier but I think he needs a volume of expansion thing.
Anyhow if he had slightly better attitude people might take him and his theory a little better.
I won't say it's impossible what he is suggesting but let just say I would like to see a hell of a lot more calculations than he has in his paper so far and if he was serious he would do them rather than complain about people who think his idea is far fetched.
Edit: BTW have a look at (http://en.wikipedia.org/wiki/(47171)_1999_TC36) thats a more interesting system because it includes a 3rd body IMO :-)
