Ask HN: Is polymimetic alloy (from Terminator 2) a physical possibility?

I understand it's likely not technically feasible right now, but suppose we're sufficient advanced, how would we go about doing it?

Some ideas I have: 1. Use quantum locking to rearrange superconducting particles by altering shape of magnetic field. 2. Tiny bots with magnets around them. Use a combination of repelling and attraction to propel themselves to wherever is needed.

I'm not a physicist, but this topic greatly interests me.