>H: Jupiter brain substrate (WAS: Goals)

Eliezer S. Yudkowsky (sentience@pobox.com)
Thu, 20 May 1999 00:25:51 -0500

Billy Brown wrote:
> O'Regan, Emlyn wrote:
> > I'm a bit worried about all this talk of Jupiter sized brains (although
> > I'm guilty of it myself).
> Me too. Obviously a device built out of degenerate matter, in the shape of
> a shell covering the surface of a white dwarf, would provide much better
> performance in a far smaller volume of space (although the mass required is
> larger by a factor of a few thousand). Come on, guys, lets see some
> imagination! ;-)

Well, I suppose neutronium is *okay*, if you're not worried about *efficiency* or anything...but Real Powers Use Monopolium. Not neutronium. Not Higgsinium. Raw, incredibly dense monopoles.

This is the story of Mel... no, just kidding. Anyway, my handy-dandy reference, "Harvard Doesn't Publish Science Fiction" by Moravec in _New Destinies III_ (it should be called _New Densities_, ha ha), says that Higgsinium (formed of pseudo-iron atoms with a nucleus of 26 negative Higgsinos and 26 protons orbiting the nucleus) is 10^18 times as dense as water. Monopolium, formed of magnetic monopoles bound by their opposite polarities instead of electrical charges, is 10^25 times as dense as water - a thimbleful weighs as much as the Moon. Switching speeds increase accordingly.

Don't tell *me* about Moore's Law running out of room.

Thus an actual Jupiter Brain, formed of Jupiter, would probably be just around a meter wide (?). You can't have a Brain that's actually the size of Jupiter because it would collapse and form a black hole, not to mention that there isn't that much mass in the whole solar system or possibly the galaxy.

Questions for Thought and Study:

  1. What is the maximum size/mass of a JB constructed of monopolium?
  2. How much computing power would it have?
  3. How much time would a unified thought take to cross the JB?
  4. How does a JB's reaction time and flops/thought compare with a human?
  5. How does strange matter compare to Monopolium?
  6. Adjust your results for relativistic slowdown due to the JB's mass.
  7. Calculate whether monopolium has a Chandrasekhar limit. Does this change the maximum?
  8. How would you detect a JB using SETI?
  9. How much energy does a JB dissipate while performing computations?
  10. What is the maximum non-hole-forming density of JBs as a function of population?
  11. At the population equalling a galactic mass, what is the time for thoughts to cross?
  12. How does the ratio compare to human thoughts vs. human speech?
  13. What are the orbital speeds necessary to prevent a collapse to the center?
  14. How fast does a JB society circulate?
  15. How long does it take for a thought to permeate society?

According to these assumptions, far from being mutually telepathic, the future may be filled with individuals far more alone than we ever were. I happen to think that Real Powers Use Alpha Points, but if anyone did the calculations above, it would probably make a nice article somewhere. Alas, I lack the physics, since a mortal has to draw the line somewhere...

        sentience@pobox.com          Eliezer S. Yudkowsky
Disclaimer:  Unless otherwise specified, I'm not telling you
everything I think I know.