Has any mathematician constructed a physical, (global), ball model of $\Bbb R^3?$

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Q: Has any mathematician constructed a physical, (global), ball model of $\Bbb R^3?$

For example, to map $\Bbb R^3$ inside $S^2$ you can do, $(x,y,z)\mapsto(x,y,z)/\sqrt{1+r^2}$ so, $\left(\dfrac x{\sqrt{1+x^2+y^2+z^2}},\dfrac y{\sqrt{1+x^2+y^2+z^2}},\dfrac z{\sqrt{1+x^2+y^2+z^2}}\right).$

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I've made a small model of $\left(\dfrac x{\sqrt{1+x^2+y^2+z^2}},\dfrac y{\sqrt{1+x^2+y^2+z^2}},\dfrac z{\sqrt{1+x^2+y^2+z^2}}\right)$ for $x,y,z \in\{-2,1,0,1,2\}$ (ie. $5^3 = 125$ points in total) and the grid lines passing trough them with red length-wise parallel lines, blue width-wise parallel lines and green height-wise parallel lines. You can download the model here and view it with View3dscene.

enter image description here Geometrically, I don't know if there's much to say about the model. The sphere which is the boundary of the ball represents infinity (the metric distance from a point in the interior of the ball to a hypothetical point on the boundary of the ball is infinite), so the closer you get to the boundary, the "denser" the points will be.

Also, parallel co-planar lines will intersect at infinity, at two radially opposite points of the sphere. enter image description here

As expected, it looks "most" Euclidean when looking from the center.

enter image description here