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Conic sections in taxicab geometry

So far all the shapes we've considered under taxicab geometry are, in Euclidean geometry, conic sections: circles, ellipses, parabolas, and hyperbolas. Let's see if these shapes are conic sections in taxicab geometry as well.

Not all cones are based on a circle, but the one used for Euclidean conic sections is. Since a circle in taxicab geometry is a square, a taxicab cone is a pyramid:

A pyramidal cone in taxicab geometry.

Plainly taxicab circles are conic sections:

A taxicab circle as a conic section of a taxicab cone.

Two-vertex parabolas might be a conic section:

A two-vertex parabola may be a conic section in taxicab geometry.

However, not just any such section will create a parabola. Only certain angles of the cutting plane or certain angles of the cone produce 45° angles at the vertices. Maybe the cutting plane has to be parallel to one side of the cone/pyramid? Perhaps the pyramid has to have a 45° or 90° apex?

Three-vertex parabolas also seem possible, with the requirement that the end rays extend parallel to each other:

A three-vertex parabola may be a conic section in taxicab geometry.

It's hard to imagine how a hyperbola could be a conic section. Hyperbolas in taxicab geometry take eight different forms, but half of them have some portion that fans out into an area. The only way a cutting plane produces an area on a pyramid is when it aligns with one of the pyramid's faces:

Conic sections can be areas in taxicab geometry, and occur when the cutting plane intersects a face of the pyramid.

For that to be a hyperbola, the sides of the cone must meet at the apex at 90°.

In addition to area problem, I don't see anywhere for a line to extend infinitely in two directions, let alone with two 45° bends in the middle. The closest we can come to a hyperbola is as a variation of the parabola above:

A hyperbola as conic section?

That uses a cutting plane parallel to the cone's axis of symmetry, as done when creating a Euclidean hyperbola. In Euclidean geometry the two components of a hyperbola are created by using a double cone, with the cutting plane intersecting both of them. We can try that in taxicab geometry too:

A double cone with a two-sided hyperbola?

It's hard to see, but the alignment doesn't quite match the form of hyperbola that it looks like it does. The cones need to be offset, something like this:

Does a double cone need to be offset to match a hyperbola?

Possibly offsetting the cones could address some of the peculiarities of hyperbolic conic sections, but it feels like adding epicycles to a bad model.

The only other conic section is the ellipse. I don't see any way to get an hexagon or octagon out of a pyramidal conic section. Euclidean ellipses are made by tilting the cutting plane from horizontal, but doing so in taxicab geometry doesn't add sides, it changes their lengths:

Cutting the cone at an angle does not produce a taxicab geometry ellipse.

Geometrically, that's a kite.

It feels safe to say that taxicab shapes aren't conic sections, but if you have further information about conic sections under taxicab geometry, please email me.