World of Ptavvs

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1. winridApr 2026
   My favorite Sci-Fi AI is probably in Larry Niven's World of Ptavvs, the "brain board". It's not covered in much depth but I like it because it's basically vibe coding GPT3.5 from 1966:

   > He read, "Time to recharge battery:" followed by the spiral hieroglyph, the sign of infinity.

   > Thud, said the brain. Kzanol read, "Re-estimate of trip time to Thrintun:" followed by a spiral.

   At the brain board he typed: "Compute a course for any civilized planet, minimum trip time. Give trip time."

   ...

   Thud! The screen said, "No solution."

   Nonsense! The battery had a tremendous potential, even after a hyperspace jump it must still have enough energy to aim the ship at some civilized planet. Why would the brain...?

   Then he understood. The ship had power, probably, to reach several worlds, but not to slow him down to the speed of any known world. Well, that was all right. In his stasis field Kzanol wouldn't care how hard he hit. He typed: "Do not consider decrease of velocity upon arrival. Plot course for any civilized planet. Minimize trip time."

   The answer took only a few seconds. "Trip time to Awtprun 72 Thrintun years 100.48 days."

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2. PaulHouleFeb 2024
   I wish Niven had been able to keep writing books on his own. I loved the Known Space books but something happened to him after 1970 that was worse than what happened to Heinlein around then. I don't think the books he wrote w/ Pournelle where anywhere near as good as Neutron Star, World of Ptavvs, etc. His great disaster short story Inconstant Moon dates from that period.
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3. KineticLensmanMar 2019
   Ditto Larry Niven's "World of Ptavvs". Written in our Cold War, set within a future Cold War between Earth and Belt and a final act that is actually described as pure Dolphin.

   And completely agree on Startide Rising. The first time I saw Dolphins in the wild I was could not help but think of ST's beautiful haiku-like Dolphin poetry

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4. optimalsolverJan 2022
   In Larry Niven's "Known Space" books [0], there was a planet where telepathy was common. Natural selection kept it in check so a hunter would only be able to nudge a prey into walking into an ambush. Then an alien exploratory vessel lands on the planet, aliens that have no resistance to telepathy are instantly controlled and you get an intergalactic slaver empire from a neolithic culture in one generation.

   So red queen effect [1]. Maybe telepathy evolves in tandem with resistance to telepathy.

   [0] https://en.wikipedia.org/wiki/World_of_Ptavvs

   [1] https://en.wikipedia.org/wiki/Red_Queen's_race

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