Graduate How can I find the collision time of 2 ellipsoids that rotate

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To find the collision time of two rotating ellipsoids, it's essential to clarify the concept of "infinite speed" as it complicates the notion of time. The discussion raises questions about the feasibility of determining a collision time when both ellipsoids are rotating infinitely fast. Participants suggest that instead of a specific time, one might consider the fraction of time during which the two ellipsoids intersect. This approach shifts the focus from a singular moment of collision to a broader understanding of their interaction over time. Ultimately, the inquiry emphasizes the need for a more precise definition of collision in the context of infinite speeds.
Guy Ab
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I have 2 ellipsoids:

Ax^2/a^2+Ay^2/b^2+Az^2/c^2=1; (*a,b,c>0 constants*)
Bx^2/a^2+By^2/b^2+Bz^2/c^2=1;
Ellipsoid A rotates around axis [wax;way;waz] (unit vector) with an infinite speed;
Ellipsoid B rotates around axis [wbx;wby;wbz] (unit vector) with an infinite speed;
[Dx;Dy;Dz] is the vector from ellipsoid A center to ellipsoid B center;
The velocity of ellipsoid A center is [VAx;VAy;VAz];
The velocity of ellipsoid B center is [VBx;VBy;VBz];

How can I find the collision time?
 
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You should clarify the question.

How does it make sense to ask for a collision "time" when things are happening at "infinite" speed? Are you seeking "the fraction of time" that two figures would have some intersection?
 

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