Damien Broderick <damien@ariel.ucs.unimelb.edu.au> writes:
> >galaxy. I think I got this from Hyperspace by Michio Kaku
>
> In Kaku's VISIONS, he cites and uses the analysis by Nikolair Kardashev and
> Freeman Dyson (first popularised by Sagan, I believe, in THE COSMIC
> CONNECTION [1975]).
>
> Type I civilisation masters all the energy available on a single planet.
> (So we're still Type 0.)
>
> Type II masters a star - using a Dyson sphere, for example.
>
> Type III exploits groups of stars, perhaps a whole galaxy.
>
> Kaku conjectures Type IV, which plays tricks with wormholes and can escape
> the death of this universe by tunneling to another.
I would say a type IV would master the universe (makes a nice progression). So Tiplerian engineering comes into this category.
There was an interesting dicussion on rec.arts.sf.science a while back about this categorization, and someone suggested that you could have a logarithmic index for the ability of a given civilization to utilize energy; this might be a more exact ranking.
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