Sunday, June 19, 2005

Qudit Naming

Entanglement Made Simple (PhysicsWeb) begs the (un)important question -- what do you call qudits with more dimensions than 3?

The accepted names are:

2 (binary) qubit

3 (ternary) qutrit

D (arbitrary) qudit

Clearly the first two come from bit and trit, the common terms in the classical domain, which are loosely based (I assume) on the Latin names for bases:

2 binary

3 ternary

4 quaternary

5 quinary

6 senary

7 septenary

8 octal

9 nonary

10 decimal

11 undenary

12 duodecimal

16 hexadecimal

20 vigesimal

60 sexagesimal

(Eric W. Weisstein. "Base." From MathWorld--A Wolfram Web Resource. http://mathworld.wolfram.com/Base.html)

If you took the boring route and named them after the Latin words, this is what you might get (your results on this [fairly pointless] exercise may vary)

4 quaternary: quatrit

5 quinary: quinit

6 senary: qusenit

7 septenary: quseptit

8 octal: quoctit

9 nonary: quonit

10 decimal: qudecit

11 undenary: qundenit

12 duodecimal: quduodecit

16 hexadecimal: quhexadecit

20 vigesimal: quvigesit

60 sexagesimal: qusexagesit

Those are mostly pretty terrible, almost as bad sounding as qualgorithm. So here's a modest proposal: instead of invoking Latin, replace the D in quDit with a number (but keep qubit and qutrit since they're pretty well accepted). e.g.:

2 (binary) qubit

3 (ternary) qutrit

4 (quaternary) qu4it

5 (quinary) qu5it

6 (senary) qu6it

10 (decimal) qu10it

16 (hexadecimal) qu16it

A bit hard to pronounce maybe, but easily recognizable in print.