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by __tmk__ 684 days ago
I would think there wouldn't be much of a difference because the smallest unit you can really work with on modern computers is the byte. And whether you use 8 bits to encode a byte (with 256 possible values) or 5 trits (with 243 possible values), shouldn't really matter?
2 comments

3 fewer lanes for the same computation. FWIW 8bits is the addressable unit. Computers work with 64bits today, they actually mask off computation to work with 8bits. A ternary computer equivalent would have 31trits (the difference is exponential - many more bits only adds a few trits). That means 31 conductors for the signal and 31 adders in the alu rather than 64. The whole cpu could be smaller with everything packed closer together enabling lower power and faster clock rates in general. Of course ternary computers have more states and the voltage differences between highest and lowest has to be higher to allow differentiation and then this causes more leakage which is terrible. But the actual bits vs trits itself really does matter.
> A ternary computer equivalent would have 31trits

I think you mean 41, not 31 (3^31 is about a factor of 30000 away from 2^64).

The difference in the number of trits/bits is not exponential, it's linear with a factor of log(2)/log(3) (so about 0.63 trits for every bit, or conversely 1.58 bits for every trit).

> ternary computers have more states and the voltage differences between highest and lowest has to be higher to allow differentiation and then this causes more leakage which is terrible

Yes -- everything else being equal, with 3 states you'd need double the voltage between the lowest and highest states when compared to 2 states.

Also, we spent the last 50 years or so optimizing building MOSFETs (and their derivatives) for 2 states. Adding a new constraint of having a separate stable state *between* two voltage levels is another ball game entirely, especially at GHz frequencies.

> because the smallest unit you can really work with on modern computers is the byte

Absolutely not, look e.g. at all the SIMD programming where bit manipulation is paramount.