Timeline for Short arc of small curvature whose every planar shadow crosses itself
Current License: CC BY-SA 4.0
5 events
| when toggle format | what | by | license | comment | |
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| Sep 15, 2018 at 5:46 | comment | added | David Eppstein | One that can be projected onto a line with no self-intersections. In this case the projection direction is again the one perpendicular to the projected curve at the (former) midpoint. You can tell that the projection onto a line has no self-intersections because the tangent vector can't turn far enough to be projected to zero. | |
| Sep 15, 2018 at 5:43 | comment | added | მამუკა ჯიბლაძე | What is a monotonic curve? | |
| Sep 15, 2018 at 5:32 | history | edited | David Eppstein | CC BY-SA 4.0 |
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| Sep 15, 2018 at 1:56 | comment | added | Joseph O'Rourke | A wild guess: $\sqrt{4 \pi} = 2 \sqrt{\pi} \approx 3.5 > \pi$ might be a lowerbound, because one needs to block all $4 \pi$ surface of a unit sphere of projection directions, and each crossing in projection identifies two points on the curve. | |
| Sep 14, 2018 at 20:25 | history | answered | David Eppstein | CC BY-SA 4.0 |