Sujet : Re: The Circles
De : dohduhdah (at) *nospam* yahoo.com (sobriquet)
Groupes : sci.mathDate : 07. Jul 2025, 00:28:53
Autres entêtes
Organisation : A noiseless patient Spider
Message-ID : <104f0rl$2gt7n$2@dont-email.me>
References : 1 2 3 4 5 6
User-Agent : Mozilla Thunderbird
Op 07/07/2025 om 01:26 schreef sobriquet:
Op 06/07/2025 om 15:13 schreef Ross Finlayson:
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
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That's like AP and his ovals.
Can you be specific? Are you denying that this is an ellipse?
[...]
y^2 + 3*x^2 = 1
Or are you claiming that this is not the shape you get when you project a unit circle (centered on the origin) in a plane z = sqrt(2)*x onto the z=0 plane?
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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.
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..., 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.
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Or, "they should've known, AP warned them."
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The Circles
Re: The Circles