Re: TECH: Fractal Tardis Brains

Robin Hanson (
Thu, 10 Jun 1999 13:05:22 -0700

On 6/10/99 Eliezer S. Yudkowsky wrote:
>Well, as soon as I read that news article, just one thought passed
>through my mind: "So much for the black-hole limits on Jupiter Brains."
> David Zindell's "computational origami" is looking more plausible all
>the time. You fold up a bunch of Jupiter brains into little Tardis
>pockets, and then they all communicate with each other in this
>meta-Jupiter brain. ...
>(Who was talking about the fundamental limits of physics during the
>Singularity Colloquium a year back? I want to hold my monthly gloat.

Actually, when I read Van Den Broeck's warp drive paper yesterday, my main criticism was that he hadn't modeled actually putting anything inside his pocket. Sure it has a diameter of 200 meters, but it is modeled as being totally empty. Since he calcualtes he needs a few grams of negative mass region, I doubt if he could put much more than a few grams of positive mass inside and keep his approximation reasonable. (I suspect more mass would just collapse to a black hole.) Also, since the surface area is only 2000 plank lengths, bandwidth between it and other places would be severely limited.

So maybe you could make a few grams filling 200 meters fly at warp speed, but that's far from a jupiter brain.

Robin Hanson   
RWJF Health Policy Scholar             FAX: 510-643-8614 
140 Warren Hall, UC Berkeley, CA 94720-7360 510-643-1884 after 8/99: Assist. Prof. Economics, George Mason Univ.