Superflip? How about SuperTwist?

[blgentry]

@Stephan: Thanks for the partial explanation. I figured you were just genius. Seriously though, many of you guys impress the hell out of me with your cube knowledge and ability.

@cmhardw: I had the same idea to do a superflip + supertwist. You obviously beat me by months or years, but it's cool that someone else thought of it. It's not exactly pretty, but it's certainly a very interesting cube state in my opinion. I wonder if you could show it to a beginner and have them understand what it means. Probably not. Oh well, it's still very cool.

Brian.

 

[mrCage]

Hi

A "supertwist" on corners does not really exist!! An edge 12-flip is a superflip because any conjugate of it is still the same edge 12-flip. Not so for corners. It is impossible to twist all 8 corners the same way (cw or ccw). The best "supertwist" i can think of is the position where all adjacent corners are twisted in opposite direction. This can be done very by a very short algorithm on a 2x2x2 cube ...

Another challenge would be to simply find THE shortest corner 8-twist

Per

PS! In the mid 80s i worked out a sequence for the "superfliptwist". Superflip and "supertwist" combined. My solution was 32 face turns but i dont have this with me at work of course. Oopss. I occasionally surf the cube during working hours. Gosh!!

 

[Stefan]

A "supertwist" on corners does not really exist!!

Yes it does.

An edge 12-flip is a superflip because any conjugate of it is still the same edge 12-flip.

According to you.

It is impossible to twist all 8 corners the same way

So what?

 

[mrCage]

A "supertwist" on corners does not really exist!!

Yes it does.

An edge 12-flip is a superflip because any conjugate of it is still the same edge 12-flip.

According to you.

It is impossible to twist all 8 corners the same way

So what?

1. No it really does not. There is nothing "super" about a random corner 8-twist. The definition of "superness" is old as rock. I think the term was coined already back in 1981 by David Singmaster.

2. It is very easy to prove this. But again i guess you object to my terminology ...

3. Hence a "supertwist" (that is invariant by conjugation) cannot exist. The proof for this is fairly easy. If both a cw and ccw rotated corner exist, swap these 2 first by some sequence. The complete conjugated sequence gives another corner 8-twist

4. Did you solve my challenge?

Per

 

[Stefan]

1. The definition of "superness" is old as rock.

Show me.

2. It is very easy to prove this.

Clarification: Of course I meant the "because".

4. Did you solve my challenge?

I believe "THE shortest corner 8-twist" exists just as much as "THE best cube".

 

[mrCage]

1. The definition of "superness" is old as rock.

Show me.

2. It is very easy to prove this.

Clarification: Of course I meant the "because".

4. Did you solve my challenge?

I believe "THE shortest corner 8-twist" exists just as much as "THE best cube".

1. I will verify this when i come home. I'm "almost 100% sure" the term superflip was coined by David Singmaster in the 1980/81 "Notes on Rubik's Magic Cube". In any case i could claim my own definition and my statement remains valid. Duh ....

4. OK fine. "A" shortest then. (you could have arrested me on metric, shortest in WHAT metric ...)

 

[Stefan]

In any case i could claim my own definition and my statement remains valid. Duh ....

Sure. Would again be valid according to you. Neither Wikipedia, nor our wiki here, nor anyone else seems to agree on that definition.

4. OK fine. "A" shortest then. (you could have arrested me on metric, shortest in WHAT metric ...)

Yep, the missing metric was what I meant. Might try a brute force search. There are some 14s, 16f and 20q. I guess QTM might be quickest to brute force because searches can be limited to 18q.

 

[mrCage]

In any case i could claim my own definition and my statement remains valid. Duh ....

Sure. Would again be valid according to you. Neither Wikipedia, nor our wiki here, nor anyone else seems to agree on that definition.

4. OK fine. "A" shortest then. (you could have arrested me on metric, shortest in WHAT metric ...)

Yep, the missing metric was what I meant. Might try a brute force search. There are some 14s, 16f and 20q. I guess QTM might be quickest to brute force because searches can be limited to 18q.

Superflip or supertwist would be too marginal for wiki. "Cubing theory" is not a vast field judging by the number of people interested. The speedcubing community could however agree on some cube-mathematical terminology. A definition of some impossible state would not be extremely useful i guess. Nevertheless "supertwist" is an obvious counterpart to superflip (which DOES exist!)


Per

 

[Stefan]

Superflip or supertwist would be too marginal for wiki.

http://www.speedsolving.com/wiki/index.php/Superflip
http://en.wikipedia.org/wiki/Optimal_solutions_for_Rubik's_Cube#Lower_bounds

 

[mrCage]

Superflip or supertwist would be too marginal for wiki.

http://www.speedsolving.com/wiki/index.php/Superflip
http://en.wikipedia.org/wiki/Optimal_solutions_for_Rubik's_Cube#Lower_bounds

OK, the term Superflip was not coined by Singmaster. But it was dicussed under another name in the before mentioned booklet. It seems Mike Reid was the one to give the 12-flip it's most common name. http://home.comcast.net/~c24m48/math/symmxm.html

Per

 

[Stefan]

It seems Mike Reid was the one to give the 12-flip it's most common name. http://home.comcast.net/~c24m48/math/symmxm.html

And have you actually checked out his post?

 

[mrCage]

It seems Mike Reid was the one to give the 12-flip it's most common name. http://home.comcast.net/~c24m48/math/symmxm.html

And have you actually checked out his post?

Why? I have skimmed through it yes. What are you getting at ??

Per

 

[Stefan]

It seems Mike Reid was the one to give the 12-flip it's most common name. http://home.comcast.net/~c24m48/math/symmxm.html

And have you actually checked out his post?

Why? I have skimmed through it yes. What are you getting at ??

You need to improve your skimming skills. Here's the only paragraph where Mike said "superflip" in that post:

very nice. now how about "superflip," and also "supertwist?" these
are also reasonable candidates for antipodes of "START." i know the
following manuever for "supertwist" (22 face / 30 quarter turns):
U F' U' (L R2 F2 B')^4 U F U'
(obtained by conjugating a manuever singmaster attributes to thistlethwaite)

Not only does he mention the supertwist right next to it, and doesn't define either in a way that would make supertwist impossible like you claim, no, he even gives an example. How could you miss that?

Oh and note that Jerry writes "Superflip (an alternate name in Singmaster is the 12-flip)". Plus even you yourself just wrote "It seems Mike Reid was the one to give the 12-flip it's most common name". So do we agree now that superflip is just a name for the 12-flip? So that supertwist is a valid name for an 8-twist?

 

[qqwref]

I have always assumed that the name "superflip" came from the fact that it flipped every edge (not just some random edge flip pattern, but the SUPER-flip pattern). The fact that it commutes with everything and is the same under any conjugation (and is thus part of the center of the Rubik's Cube group) are very interesting, but are NOT necessary for the name to make sense.

(L R2 F2 B')^4

This is an AWESOME supertwist alg.

 

[mrCage]

It seems Mike Reid was the one to give the 12-flip it's most common name. http://home.comcast.net/~c24m48/math/symmxm.html

And have you actually checked out his post?

Why? I have skimmed through it yes. What are you getting at ??

You need to improve your skimming skills. Here's the only paragraph where Mike said "superflip" in that post:

very nice. now how about "superflip," and also "supertwist?" these
are also reasonable candidates for antipodes of "START." i know the
following manuever for "supertwist" (22 face / 30 quarter turns):
U F' U' (L R2 F2 B')^4 U F U'
(obtained by conjugating a manuever singmaster attributes to thistlethwaite)

Not only does he mention the supertwist right next to it, and doesn't define either in a way that would make supertwist impossible like you claim, no, he even gives an example. How could you miss that?

Oh and note that Jerry writes "Superflip (an alternate name in Singmaster is the 12-flip)". Plus even you yourself just wrote "It seems Mike Reid was the one to give the 12-flip it's most common name". So do we agree now that superflip is just a name for the 12-flip? So that supertwist is a valid name for an 8-twist?

Hmm. Empirically my odds are bad for not accepting that definition of a supertwist. But i still insist that this use of "super" breaks the spirit of its original meaning. Oh well, not a big deal really.

One can SUPERTWIST a pyraminx, im fine with that

Per

 

[Stefan]

(L R2 F2 B')^4

This is an AWESOME supertwist alg.

Haha, I need to improve my skimming skills as well. Didn't even notice that this middle part is a supertwist and how nice it is.

Then again, Mike's conjugation shows that he had a particular 8-twist in mind, not just any, so apparently our usage of "supertwist" does differ from the original meaning. Looks like it only referred to the one with adjacent corners twisted differently.

Also, since he didn't tell anything about the superflip and didn't clearly define the supertwist, I do get the feeling that that post was not where these terms were first introduced.

 

[d4m4s74]

Stephan, I don't understand how you figure out things like this.

I'm genius, that's all.

how bout (((U R U' R)2 D (R U R' U')2 D)2 Y2)2

Even if you change the wrong R to R' so it doesn't scramble the cube anymore, this only twists four corners.

Why don't people just check their goddamn algs before they post them? Try these:
http://thearufam.brinkster.net/cube/wrapplet.asp
http://alg.garron.us/

And blgentry, these tools are the real way I figure these things out. I do *not* really repeat random moves 140 times myself. I let the program do it in an instant. Using that, it's mostly trial and error with a little bit of thinking.

with exception of the R/R' mistake it seems to work
the only mistake is that Y should have been a z or x

 

[mrCage]

Hi

Here is what i found for the "nearest supertwist" algorithm. Every adjacent corner twist in opposite direction.

I did not have time to let CubeExp run to completion on this one though:

U2 L2 B L2 R2 D2 U2 B2 F' R2 U L2 R2 B2 F2 D' (16f)

[U2 L2 B m2 e2 B2 F' R2 U m2 s2 D' (12s)]

Its qtm is quite poor however ... It seems possible to grasp how this one works

Per

 

[rokicki]

16f is optimal for that position; 22q is optimal as well:

U2 R U- F- D- R- U- R- B D- F2 L F- U- B- L- F- L- D B-

 

[Cameron Pearce]

I made an account just to share this:

(([[[R: U]: U']: D] D)2 Z2)2

It is the most pattern based alg that I could come up with (I've come up with MANY) and it seems to compact down quite nicely.