Hey David, doing the 5x5x5 blindfolded is certainly not impossible, and in fact a number of people have done it. See http://www.speedcubing.com/records/recs_bf_555.html
As far as how exactly you do it, you don't update the cube in your head with every turn, you solve with longer sequences that move only 3 pieces at a time (or flip 2 pieces at a time). These are almost always intuitive commutators (permutations in the form X Y X' Y' where X and Y are two separate permutations). So for example if I want to cycle just 3 wing edges on a 5x5x5, and change absolutely nothing else on the cube (this is the key part) then I could do something like this R' d R U R' d' R U' If you do this on a 5x5x5 you'll see that it only affects 3 edge pieces, and if you look deeper you'll see that absolutely nothing else on the whole cube changes. So what you do is memorize how the different types of pieces cycle back to their original places. There are only 5 types of pieces on a 5x5x5, and they are corners, central edges, wing edges, and two types of centers (called +centers and Xcenters). If you memorize the cycles of each piece type, as well as the orientations of the corners and central edges, you can use moves to either move or flip pieces without affecting anything else. For example if I want to flip two central edges without changing anything else I can do R' e' R2 e2 R' U R e2 R2 e R U' This long move is just a commutator of the form X Y X' Y' X = R' e' R2 e2 R' Y = U and you can see how it is made. Check out the blindfolded group at http://games.groups.yahoo.com/group/blindfoldsolving-rubiks-cube/ if you are interested in learning more about blindfold solving. So in short it's definitely not impossible to do a 5x5x5 blindfolded. Not easy, yes, but definitely possible. Hope this helps, Chris --- In [email protected], David Pritts <[EMAIL PROTECTED]> wrote: > > I noticed on the WC2005 website that only 3 people attempted solving the 5x5x5 cube blindfolded, and none of them finished... this didn't surprise me in the least, of course, since the whole concept is absurd. I determined that it wasn't possible. > > Then I saw on Stephan's site that he apparently set a world record for solving the 5x5x5 blindfolded, in 2.5 hours... > > Although I don't ever plan to try something this absurd myself at any point in my life, I would be delighted and fascinated to hear exactly HOW you would do something like that... IE, do you (after every move), go through all the sides, picturing what colors were placed where as a result of your move? Is your memory THAT good? > > How many people have ever done this? > > Amazing. > > David > > > --------------------------------- > Yahoo! Photos > Ring in the New Year with Photo Calendars. Add photos, events, holidays, whatever. > > [Non-text portions of this message have been removed] > Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/speedsolvingrubikscube/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
