Re: The Circles

On 07/01/2025 04:29 AM, sobriquet wrote:

Op 01/07/2025 om 07:16 schreef Ross Finlayson:

On 06/30/2025 11:29 AM, Chris M. Thomasson wrote:

On 6/28/2025 8:38 PM, Ross Finlayson wrote:

Oh, been a while, figure I'll post.

[...]
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An ellipse is nothing more than a circle projected in 3d? ;^)
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That's frivolous.
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An ellipse is constructible from a loop of string and two pegs.
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An image of a circle onto a plane as projected from
an incident angle via 3D:  is not an ellipse, either.
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Ask your shadow.
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Looks like an ellipse to me:
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https://www.desmos.com/3d/syqqdp9cef?translucentSurfaces

That's like AP and his ovals.
There are ellipsoids of various sorts,
and as for oblate spheroids, what "a
traditional section of conics, ..., and
a flashlight through it projected onto
various surfaces", may result.
..., And the entire modern mathematical problem
of elliptic curves and elliptic curve cryptography
is broken by a guy with a sufficiently large setup
of conic sections and flashlight and backdrop.
Or, "they should've known, AP warned them."