7 ms·
I assume the time depends very much on the initial state.
by callesgg 11y ago
I assume the time depends very much on the initial state.
- baddox 11y agoI wonder how they set the initial state. I think it's fairly easy to calculate the minimum number of moves required to solve from a given state, so you'd think they would control for this.
- rusbus 11y agoMost states can be solved in around 21 moves by the best computer algorithms, but the fastest humans usually solve it in significantly more.
- deleted 11y ago[deleted]
- atom-morgan 11y agoThe initial state is a random computer generated scramble. It's easy to calculate if you have a computer but it isn't easy when you have to do it in your head.
- harryh 11y agoIt is, in fact, not easy at all to calculate that. https://en.wikipedia.org/wiki/God%27s_algorithm https://en.wikipedia.org/wiki/God%27s_algorithm (There isn't as much info as there should be on that Wikipedia page but it was an open area of research for decades.)
- deleted 11y ago[deleted]
- baddox 11y agoIsn't it though? I thought the hard part was proving the minimum number of moves that can solve all possible initial states. Korf's algorithm and several subsequent improvements seem to be able to find the minimum number of moves to solve any given initial state.
- harryh 11y agoA yes. You are correct. Finding minimum # of moves from a single state = not so hard. Finding the worst possible state (the state where the minimum # of moves is a maximum) = pretty hard, though now solved.
- rusbus 11y agoThere are standard randomized scrambles generated for competitions. Most competitions use some subset of 12 solves and take the average, although this appears to be the single solve record.
- brainburn 11y agoAgreed. More interesting is the variant where people try to solve a cube in as few moves as possible.
- atom-morgan 11y agoSpeedcuber here: each competitor starts with the same initial state for each solve in their best of X. Yes, there is some luck involved but it's distributed equally.
- orblivion 11y agoPer competition though, not across competitions, which is relevant WRT world records.
- mannykannot 11y agoYes - the fact that the record was broken twice in this one competition suggests that its particular initial state should be analyzed for solvability before we assume that we have entered 'a new chapter for speedcubing.'
- level3 11y agoThe two records were actually on different scrambles (i.e. different initial states). It's one thing if there was a particular scramble that everyone was solving faster than usual, but that wasn't the case here.
- atom-morgan 11y agoWell, yeah. You can't account for everything. Traditional sports don't consider elevation, air quality, wind, etc.
- hyperpape 11y agoTo an extent. Road race world records are only valid if they fall within certain limits of elevation change. You can run slightly downhill, but can't descend 500 meters. Ditto for tailwinds, I believe.
- mihaifm 11y agoWind speed is accounted for in athletics. Records won't get validated if there is a strong tail wind.
- iraphael 11y agoSort of, technically, no state needs more than 20 moves to be solved (but finding that optimal solution is kinda hard for humans). So while luck can play a part (i.e.: you may get a configuration that only requires three moves), it's much more a matter of skill to find those 15, 20, 23 moves. http://www.cube20.org/ http://www.cube20.org/ https://www.youtube.com/watch?v=yF2J39Xny4Q https://www.youtube.com/watch?v=yF2J39Xny4Q
- bpicolo 11y agoThe strategies humans use to solve it are not nearly so optimal in terms of number of moves. More like 50-100 for a typical solve.