[ExI] mbrains again: request

[spike]

>... On Behalf Of Eugen Leitl
Subject: Re: [ExI] mbrains again: request

On Wed, Sep 28, 2011 at 10:48:28AM +0100, Anders Sandberg wrote:
> spike wrote:
>>
>>
>>> Here’s the discovery. As far back as ten years ago, I was fooling 
>>> with MBrain orbit calculations and discovered that an MBrain can move 
>>> an entire star. This past weekend, I was using the same equations I 
>>> derived back then and discovered the original comment was an 
>>> understatement. Not only can an MBrain move a star, it must... s




>> ...Just absorbing and re-radiating the luminosity as blackbodies produces a nice equilibrium temperature as far as I can see - ...Anders

>...You need to use photon momentum (no need to waste mass) for active node orbit control, as otherwise the node cloud orbits will degenerate and you'll get internode collisions, which can cause a runaway collision catastrophe by way of fragments and turn your node cloud into a dusty fragment cloud...

Hmmm, the adjacent rings have very low relative velocity.  I need to refresh my memory from a long time ago, but a typical design had a ring of MNeurons spaced at one meter with the next ring a meter larger in radius tilted at a microradian.  The relative velocity of an MNeuron in adjacent rings was on the order of a few cm per second.  Wait, I might be able to do that to a single digit in my head: a microradian at I AU is about 150 km and it has three months to get there is about 1.5e5 meters and has about 8e6 seconds to get there and since it is a sinusoid you multiply by pi so ja, I am getting about 6 cm/sec relative velocity without messing up an envelope.  

6 cm/sec, ha!  Childs play.  I see no reason why we would ever risk a runaway collision catastrophe.

>...Is it even possible to push the entire assembly by emitting radiation mostly in one direction, climbing up in a higher orbit half the time, and descending down the other half?

Ja I don't see why not.

>...It's probably analytically too hard, so somebody could model it... Eugen* Leitl

I am already working on it against time pressure.  The pitch is on 4 November, and I need to have the answers in time to get the paper to the printers.  My spreadsheets for equilibrium temperatures are not as solidly grounded as my orbit mechanics.  {8-[

spike