If I wanted to tie a loop in the middle of a line I’d use an alpine butterfly. https://www.animatedknots.com/alpine-butterfly-loop-knot

Presumably to avoid ambiguity as to whether the thing to exponentiate is 27 or -27.

Just tether the middle to the moon instead of the balloon.

If it’s interdimensional you probably only need one RV, just outfit them differently in each dimension.

It uses energy to hold in place.