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The argument has been made that the 2x2x2 cube (or really any 2Nx2Nx2N)

cube cannot have the "symmetry of the cube". In order for a real

2x2x2 cube to have the "symmetry of the cube", you would have to

adopt unreasonable rules, such as no rotations (or if you use

rotations they have a cost of at least 2) and the cube is only solved

when the colors are oriented properly. But a 2x2x2 cube certainly

feels like a real cube when you hold it in your hands. I offer the

following interpretation that "sort of" gives the 2x2x2 cube the

symmetry of the cube. Since I will only be talking about the

2x2x2, I will simplify the notation by talking about C, G, Q, etc.

rather than C[C], G[C], Q[C], etc.

As I have discussed several times before, my favorite model for the

2x2x2 is G/C (or CG/C, if you prefer; G=CG for the 2x2x2).

The group operation is (xC)(yC)=(uv)C, where u and v are the elements of

xC and yC, respectively, which fix a particular corner. (xC)(yC)=(xy)C

doesn't work because C is not normal. There is an obvious isomorphism

between G/C and <q_i, q_j, q_k>, where the three q-turns are those which

fix the same corner as the selection function for u and v.

There are eight corners, and hence there are eight conjugate selection

functions and eight conjugate subgroups G_m of the form <q_i, q_j, q_k>

which fix a particular corner. If you think of mapping G/C

simultaneously and in parallel to the all the elements in the set

{G_1, G_2, G_3, G_4, G_5, G_6, G_7, G_8}, then in a loose sense you

have preserved the cubic nature of the problem. That is, none of

the individual G_m's have the same symmetry as the cube, but in a loose

sense the entire collection {G_m} does.

= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Robert G. Bryan (Jerry Bryan) (304) 293-5192 Associate Director, WVNET (304) 293-5540 fax 837 Chestnut Ridge Road BRYAN@WVNVM Morgantown, WV 26505 BRYAN@WVNVM.WVNET.EDU