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# 2^64 bytes is enough for any human

## 2^64 bytes is enough for any human

Posted Apr 20, 2004 16:47 UTC (Tue) by zooko (subscriber, #2589)
In reply to: 2^64 bytes is enough for any human by giraffedata
Parent article: The Grumpy Editor goes 64-bit

At some point, the "we'll always need more" belief has to be wrong. For example: do you think we'll need more than 2^128 memory? I don't. How many atoms of matter are there in the universe?

2^64 bytes is enough for any human

Posted Apr 23, 2004 0:03 UTC (Fri) by chant (subscriber, #20286) [Link]

First, imagine some sort of 3-d movie.
Then, an interactive 3-d movie.
Then consider a large-scale 3-d movie; i.e. modelling what happens to each of those atoms in the universe over time.
Or, perhaps, modelling the little tiny components (and sub-components ad nauseum) of even one of those atoms. The possibilities are endless.... and perhaps, storing the 'feel' & phyiscs reacions of physical textures, the bonds between each of those atoms, etc.

Or....on another order of magnitude altogether, the binaries for Windows U[niverse]E.

:)

2^64 bytes is enough for any human

Posted Apr 27, 2004 21:01 UTC (Tue) by slamb (guest, #1070) [Link]

The point is not whether or not it would be useful to have an accurate model of the universe, but that it is impossible. Clearly you can't do better than (or even as well as) harnessing the largest set of good quantum numbers of every particle in the universe. (Your computer has to be in the universe!) So by examining the number of particles in the universe, you can come up with a number that is larger than the maximum possible storage space of a computer. Take the base-2 log and you've got an inexhaustible address space.

I've seen discussions of this number before, but I don't remember the result. But I seem to recall it being less than 2^128; thus, a 128-bit address space is good enough for anyone. Really.

There are other arguments based on thermodynamics limiting the complexity of a computer. Google for discussions of thermodynamics and reversible vs. irreversible computers and you'll see what I mean.