Re: What shape is this.



On Fri, 17 Apr 2009 02:16:02 -0700 (PDT), the following
appeared in talk.origins, posted by Bill254
<spintronic@xxxxxxxxxxx>:

On Apr 17, 12:03 am, Bob Casanova <nos...@xxxxxxxx> wrote:
On Wed, 15 Apr 2009 10:20:45 -0700 (PDT), the following


I would define a torus as a "circle looped in a circle".
Where *loop* takes on the connotation of *blowing a bubble*.

But I would not define the (hole in the middle) as a circle.

The projection of the inner edge of the torus onto a plane
is a circle.


A torus has no edges.

OK, so you're not familiar with the concept of projection
onto a plane. Since a circle also has no edges, it's also
impossible to create a projection of a circle onto a plane,
right? Hint: The answer is "No, it's quite possible". And
the projection of a torus onto a plane is a pair of
concentric circles; the projection of the "hole" is the
inner circle.

And your delusions are projecting.


And for lesson 101 in hypocrisy we have...

So we can add "hypocrisy" to the list of terms you don't
understand...

Since when we look "down" onto the torus our
eyes are essentially viewing that plane it's perfectly
reasonable, although not mathematically rigorous, to
describe the "hole in the middle" as a circle.

Ah. Bun that would be *totally* "mathematically ridiculous" to
do the same with the earth?.

Of course not. Ummm... Who mentioned the Earth, and what's
the relevance to a projection of a torus onto a plane, other
than the fact that both are mathematically valid procedures?
And where did the quote "mathematically ridiculous" come
from? *I* certainly didn't use it in this thread. Perhaps
that's where your spurious "hypocrisy" accusation came from;
your failure to remember who said what, and in what thread?
--

Bob C.

"Evidence confirming an observation is
evidence that the observation is wrong."
- McNameless

.



Relevant Pages

  • Re: Is infinite Euclidean space non-euclidean?
    ... circle will also then, as you say, have an infinite length. ... of projecting the sphere, ... You can assume that the projection is to a plane which is tangential ...
    (sci.logic)
  • Re: Oblique torus slice: intersecting circles
    ... let the coordinate system be such that the torus has ... so that the torus may be constructed by taking a circle with center ... The intersection of the torus with a plane at distance z above the XY ...
    (sci.math)
  • Re: cylindrical star track 2-D projection shapes
    ... circles, ellipses, elliptical arcs, straight lines, ... A photograph is a projective transformation onto a plane: ... and the circle is not the celestial equator). ... the projection is a hyperbola. ...
    (sci.math)
  • Re: What shape is this.
    ... The projection of the inner edge of the torus onto a plane ... A torus has no edges. ... describe the "hole in the middle" as a circle. ...
    (talk.origins)
  • Re: 3D Geometry: Torus-Line Collision
    ... What you mean "generating circle in 3-space"? ... so that its center is on the larger one, and the plane ... (otherwise one doesn't quite get a torus). ... Point P is an arbitrary point in 3-space; we want to find the distance ...
    (sci.math)