Why binary and not ternary computing?

Question

Isn\'t a three state object immedately capable of holding more information and handling larger values? I know that processors currently use massive nets of XOR gates and th

Answer 1

You should read the articles about a russian ternary computer:

• http://www.computer-museum.ru/english/setun.htm
• http://en.wikipedia.org/wiki/Setun
• http://de.wikipedia.org/wiki/Setun

Answer 2

Screwball's reply is correct and corrects some of the misstatements offered here. Those who replied about fractional positive values completely missed the concept of the ternary system which is based on 0, +1 and -1. When first constructed by the Russians in the 1950's, the competition between USSR and USA was intense. I suspect that politics between the two had a lot to do with the USA's binary's eventual popularity over the USSR's ternary.

From what I've read, there are some ternary computers in use. Moscow has some in use at their university and IBM has some in its labs. There are references to others, but I couldn't distinguish how serious they are, or if they are just for experimentation or play. Apparently they are much less costly to build and they use far less energy to operate.

Answer 3

I think that ternary would be more efficient. It just never became popular. Binary took the stage and now a switch to ternary would be a change of everything we know.

Answer 4

A lot of it has to do, I am pretty sure, with error checking of digital signals. For example, in quantum computing this task is nearly impossible, but not impossible, to achieve do to the non-cloning principle, but also due to the fact that there are an increased number of states. For two states the process of error checking is not trivial, but it is relatively easy. For three states error checking becomes infinitely harder. This is also why analogue computers with an nearly infinite amount of states were ruled out.

If you are interested in Quantum Computing though look into sphere packing and quantum error checking, some pretty neat stuff there.

Answer 5

• It is much harder to build components that use more than two states/levels/whatever. For example, the transistors used in logic are either closed and don't conduct at all, or wide open. Having them half open would require much more precision and use extra power. Nevertheless, sometimes more states are used for packing more data, but rarely (e.g. modern NAND flash memory, modulation in modems).

• If you use more than two states you need to be compatible to binary, because the rest of the world uses it. Three is out because the conversion to binary would require expensive multiplication or division with remainder. Instead you go directly to four or a higher power of two.

These are practical reasons why it is not done, but mathematically it is perfectly possible to build a computer on ternary logic.

Answer 6

Lots of misinformation here. Binary has a simple on/off switch. Trinary/Ternary can use one of 2 modes: Balanced aka -1, 0, +1, or unbalanced 0, 1, 2, but is not simply on or off, or more correctly, has 2 "on" states.

With the expansion of fiber optics and expansive hardware, ternary would actually take us to a much more expansive and faster state for a much lower cost. Modern coding could still be used (much like 32 bit software is still able to be used on 64 bit hardware) in combination with newer ternary codes, at least initially. Just need the early hardware to check which piece of info coming through, or the software to announce ahead of time if it is a bit or a trit. Code could be sent through 3 pieces at a time instead of the modern 2 for the same or less power.

With fiber optic hardware, instead of the modern on/off binary process, it would be determined by 0=off and the other 2 switches as orthogonal polarizations of light. As for security, this could actually be made massively more secure for the individual as each PC or even user is set to a specific polarization "specs" that is only to be sent/received between the user and the destination. The same would go for the "gates" with other hardware. They would not need to be bigger, just have the option for 3 possibilities instead of 2.

There has even been some theories and even possibly starting some tests on the Josephson Effect which would allow for ternary memory cells, using circulating superconducting currents, either clockwise, counterclockwise, or off.

When compared directly, Ternary is the integer base with the highest radix economy, followed closely by binary and quaternary. Even some modern systems use a type of ternary logic, aka SQL which implements ternary logic as a means of handling NULL field content. SQL uses NULL to represent missing data in a database. If a field contains no defined value, SQL assumes this means that an actual value exists, but that the value is not currently recorded in the database. Note that a missing value is not the same as either a numeric value of zero, or a string value of zero length. Comparing anything to NULL—even another NULL—results in an UNKNOWN truth state. For example, the SQL expression "City = 'Paris'" resolves to FALSE for a record with "Chicago" in the City field, but it resolves to UNKNOWN for a record with a NULL City field. In other words, to SQL, an undefined field represents potentially any possible value: a missing city might or might not represent Paris. This is where trinary logic is used with modern day binary systems, albeit crude.