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by Retric 1014 days ago
The question opens with a question about the material properties of a physical object and many of the replies address that.

As a pure math problem it’s got a few constraints such as the track not physically intersecting with itself which go beyond the stated question.

So yes it’s a toy problem, but one constrained by real world objects.
2 comments
mhb 1014 days ago
Yeah, that's human interest to get you interested in the problem and how it occurred to the author. Do you think the trolley problem is about trolley cars on rails with switches?
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Retric 1014 days ago
The most upvoted response was objectively wrong due to real world constraints.

The real world is irrelevant in the trolly problem or the 4 color theorem etc.

You may personally be interested in it as a purely mathematical problem, but he’s looking for a real world answer so poor abstractions are useless. On the other hand “I would first check for track flatness. When locked in with extra effort, the loop will warp a little, basically going into 3d instead of flat 2d.” is a useful shortcut.

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mhb 1014 days ago
> he’s looking for a real world answer

Based on his history in StackExchange, it is unlikely Lezzup is looking for a real world answer. The top tags of his posts are: mathematics, sudoku, geometry, logical-deduction, sequence, and enigmatic-puzzle.

https://puzzling.stackexchange.com/users/84683/lezzup

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Retric 1014 days ago
“I am sure this could be calculated mathematically, but I prefer a more quick, practical way.”
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mhb 1014 days ago
As it seems that English is not his first language, and that quote you offered appears to contradict "I know I could just take one piece out, and put it back in to feel it myself, but I am looking for a more logical way, so I am able to reason it", and based on the provenance of his other postings, these appeals to contort the question into some kind of uninteresting material science one are not credible.
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Retric 1014 days ago
There’s no contradiction to “logical methods” including things like noticing the pieces curve into 3D space because they don’t fit together. Saying you don’t want to rely on taking it apart doesn’t invalidate simple inspection.

The fastest solution is going to be a combination of heuristics and multiple forms of mathematical modeling. Something like 1 does it look reasonable, 2 do the internal angles add up correctly, then 3 a more precise assessment based on actual curves and piece lengths. Doing 3 when it already failed 2 is redundant.

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hgsgm 1014 days ago
It's a real world problem, but one constrained by toy objects.
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