I’m not a betting type, but if I had to take a bet I would expect it to be ~”and this is how the conditions of the Big Bang can be recreated and exploited to make something that looks like a star but which will exist forever. Also the interior of our fake star is now a new universe 50 billion light years across even though the outside circumference is ten light seconds.”

Not very useful for cell-scale engineering. Might count as “magic”, but the bigger-inside thing is a serious idea for making the Alcubierre drive less unphysical.