Friday, December 30, 2022

Another Theorem By Changing The Question

 Suppose it is established that \(n\) runner running about a unit circle with arbitrary constant speeds, \(v_i\), one just experienced a moment of loneliness, and is at least \(\cfrac{1}{n}\) away from the closest runner.


We add the next \((n+1)\) runner, with relative speed zero, where all other runners take reference, right in between and achieve a least distance of \(\cfrac{1}{2n}\).  This \((n+1)\) runner is at the origin zero (starting point).  The added \((n+1)\) runner still has arbitrary speed, distinct and constant.

This is the trivial case of \(n=3\).

Since     \(\cfrac{1}{2n}\lt\cfrac{1}{(n+1)}\)

for \(n\gt 2\)

Adding the next \((n+1)\) runner becomes trivial, and with the trivial case of \(n=3\), by induction the conjecture is true.  The constraint is still a least distance of \(\cfrac{1}{n}\), it has not been changed to \(\cfrac{1}{2n}\).

What?  Using relative speeds is not suppose to change any aspect of the analogy.

 Happy? 

Note: All speeds changed by a constant, but the transition of time has no bearing here. The origin is rotated by a constant.  The circle is rotating at the reference speed, speed of the \((n+1)\) runner.  Starting time is later for all.