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One-Answer 4x4 Question Thread

xyzzy

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For 4 by 4, PLL parity is considered not to be real parity
Depends on who you ask, and also the context in which you're asking. I think the people who say this don't really realise the implications of claiming that PLL parity isn't truly "parity" – as you've noticed, it leads to the weird conclusion of swapping two corners not really being "parity" either.

In the context of 4BLD, it's reasonable to consider PLL parity to not be a thing, since you're directly solving the edge pieces rather than doing edge pairing. Instead, there's corner parity: when you have an odd number of corner targets. Your example of swapping two corners falls into this category, but so does something like a T perm (or even more simply, a single U move).

In the context of a reduction method (or a variant thereof, like Yau or Hoya), there are two parity problems: one where the parity of the number of bad edges is wrong (aka "OLL parity"), and one where the permutation parity of the corners and edge pairs is wrong (aka "PLL parity"). The former type of parity can also be explained in terms of the permutation parity of the individual edge pieces, but you can't break down the definition of "PLL parity" any further (*). This tends to confuse people who think that parity can only apply to a single piece type, or only to single pieces. (You can blow their minds by handing them a 6×6×6 supercube with two pairs of oblique centres swapped. It's not solvable.)

(*) Not for the usual speedsolving methods anyway, but in the computer-solving method Three-Phase Reduction, it is possible to describe PLL parity in terms of single pieces (although it still involves two piece types). In the second reduction phase, the parity of the edge pieces is solved, so OLL parity can never happen; the second phase also splits the 24 edge pieces into two orbits of 12 pieces each. In the third phase, edge pairing is done, while also ensuring that the parity of the corners and one of the edge orbits (doesn't matter which) is solved, which ensures that PLL parity can never happen.
 
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Gerry

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I just got my first 4x4 (YJ MGC), and I'm wondering if it's normal for it to be a lot more picky when turning.

I have a 2x2, and a few 3x3s, and they all are fast, corner cut great, and are generally very forgiving.

This 4x4 seems super weird to play with after using the 2x2 and the 3x3. The middle layers have stronger magnets, and are much harder to turn. Also the cube flexes weird even though it is magnetic. The corner cutting is almost nothing, and if a turn is short, the cube feels like it's going to explode. Is this the norm? Or am I just failing to set it up? It reminds me of watching people solve old rubiks brand where they have to square up the cube between turns.
 
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How do you permutate the LL on 4x4 when doing lbl? Usually I'll get parity or a U perm but it's only half of the pieces. In other words only half of the pieces are unsolved like if you have Blue top and have a U perm one of the sides will be Orange, White, Orange, Orange. Instead of Orange, White, White Orange. My question is how do you do a cycle of single pieces, not dedges?
 
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How do you permutate the LL on 4x4 when doing lbl? Usually I'll get parity or a U perm but it's only half of the pieces. In other words only half of the pieces are unsolved like if you have Blue top and have a U perm one of the sides will be Orange, White, Orange, Orange. Instead of Orange, White, White Orange. My question is how do you do a cycle of single pieces, not dedges?
isn't that just a slice commutator?
 
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my bad. I mentally didn't want to process that someone was actually doing LBL.
It's less lbl and more like doing cross followed by pairing a corner with an edge than permutating the other edge to the opposite side then solving with commutators. Than you move on to Oll which usually ends in a modified version of ELL, then doing PLL, plus the case I'm stuck on. So you know basically lbl, not really what I meant when I said lbl was in the style. i:e solve it without Reduction.
 
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The concept is identical to a 3x3 edge commutator, if you don't know that, there are a lot of yt vids explaining how to do a commutator
If your answer is jusT wahtc it on yT! Then just don't answer that does not help at all. I am asking because I don't have access to YT on my lapop due to Firewall. I was specifically asking for help not if anybody could tell me where to find a resource, now if you gave me a direct resource and explained it that would be different.
 
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If your answer is jusT wahtc it on yT! Then just don't answer that does not help at all. I am asking because I don't have access to YT on my lapop due to Firewall. I was specifically asking for help not if anybody could tell me where to find a resource, now if you gave me a direct resource and explained it that would be different.
well you should specify that then
 
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Did you even read the whole thing? I did not ask if anybody had sources, I asked if anybody knew as in they could tell me directly not through a video.
You simply said "My question is how do you do a cycle of single pieces, not dedges?". Is it my job to know that specific request that you just stated? If you ask a question, like that, of course I am first going to question if you had searched it up just to save time.
 
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You simply said "My question is how do you do a cycle of single pieces, not dedges?". Is it my job to know that specific request that you just stated? If you ask a question, like that, of course I am first going to question if you had searched it up just to save time.
How do YOU do a cycle of dedges, not "does anyone know how to do a cycle of dedges", if I had used that wording your response would be perfectly fine but I did not say that.
 
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How do YOU do a cycle of dedges, not "does anyone know how to do a cycle of dedges", if I had used that wording your response would be perfectly fine but I did not say that.
Asking in that way is very common and a lot of people who ask in that way would be fine in the way I responded, at least in my experience. It's unnatural and disrespectful to aggressively dismiss my answer and back it up with an invalid reason. I'm getting tired of this argument, so please let's just stop now If you want to know how to do a slice commutator, be respectful about the responses, even if you think it's unhelpful.
 
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So today I got my first 4x4 and within 2 hours I was able to solve it so then I was playing around with it and I get this weird pll case I don’t know if I should call parity but yeah can someone reply to this with a solution please or did I mess up the edge paring, please take your time to reply and thank you. Also before you say it’s a Ua case or something like that it’s not for someone reason two sides are solved while the others have opposite colored edges on top8E58ADB9-D89E-4540-A0DF-B213FABC62C5.jpegE0986F73-70EE-4499-AD3E-8C150E04389A.jpeg
 
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