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Dec 3, 2022 at 18:36 history edited Jacob Helwig CC BY-SA 4.0
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Dec 3, 2022 at 18:26 vote accept Jacob Helwig
Dec 2, 2022 at 17:06 history edited Jacob Helwig CC BY-SA 4.0
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Dec 1, 2022 at 23:47 comment added Daniel Sebald @MaartenHavinga SO(3) actually does contain S3, inside A5.
Dec 1, 2022 at 21:47 vote accept Jacob Helwig
Dec 2, 2022 at 17:07
Dec 1, 2022 at 21:30 vote accept Jacob Helwig
Dec 1, 2022 at 21:47
Dec 1, 2022 at 19:45 answer added Maarten Havinga timeline score: 1
Dec 1, 2022 at 19:13 comment added Maarten Havinga @JacobHelwig it seems to me more that you mean 90 degree rotations of functions from $Z_N^3$ to some other algebra, where $Z_N$ is the integers modulo $N$. For you cannot apply 3D rotations to $N×N×N$ tensors in general.
Dec 1, 2022 at 8:47 review Close votes
Dec 10, 2022 at 3:03
Dec 1, 2022 at 0:26 comment added Jacob Helwig @LSpice Sure, I edited my question
Dec 1, 2022 at 0:26 history edited Jacob Helwig CC BY-SA 4.0
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Dec 1, 2022 at 0:24 comment added Jacob Helwig @MaartenHavinga I do not follow your comment - is my proposed answer right?
Dec 1, 2022 at 0:23 comment added Jacob Helwig @GerryMyerson Similar to how $\mathbb R^{5\times5}$ is the space of $5\times5$ matrices, $\mathbb R^{5\times5\times5}$ is the space of $5\times5\times5$ tensors. I'm imagining rotating a tensor $X$ by a rotation tensor $R$, similar to a rotation matrix. Then what I mean by unchanged is that $R\cdot X = X$
Nov 30, 2022 at 22:54 comment added Gerry Myerson I don't understand the notation. If $N$ is, say, $5$, then $X$ is a cube in the $125$-dimensional space ${\bf R}^{5\times5\times5}={\bf R}^{125}$. I don't know what it means for $X$ to be a cube in this space. So, maybe you mean a cube in ${\bf R}^3$, measuring five on each side. Then what does "the result is unchanged" mean? What result? Unchanged from what?
Nov 30, 2022 at 20:37 comment added Maarten Havinga No wait. Since N is odd, elements at an n-th index can be rotated to other elements at an n-th index: (3,1,n) to (3,n,1) as x-axis rotation. That only counts for these edge cases with a 1 index and an n index.
Nov 30, 2022 at 20:20 comment added Maarten Havinga Since SO(3), the group of all rotations in 3D, contains A3 but not S3, the odd permutations are excluded. So there are twice as much 3 different index unique elements. I think you're correct after changing that.
Nov 30, 2022 at 17:53 history edited Jacob Helwig CC BY-SA 4.0
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Nov 30, 2022 at 17:46 history edited Jacob Helwig CC BY-SA 4.0
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Nov 30, 2022 at 17:23 history edited Jacob Helwig CC BY-SA 4.0
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Nov 30, 2022 at 17:00 history edited Jacob Helwig
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S Nov 30, 2022 at 16:59 review First questions
Dec 1, 2022 at 8:26
S Nov 30, 2022 at 16:59 history asked Jacob Helwig CC BY-SA 4.0