Ugh.  Head has things, can't make words behave.
Vacuum 'bubble': what makes it look like it extracts energy from from nothing?
Well, this may be due to time not playing along with the expansion of space.
The expanding bubble may only represent space being distorted, and not time within the distortion volume.
Or, time does expand with the bubble, but not 'properly', so the expansion energy is more than should be.
Or, the time that the bubble exists is a 'window' that all the expanding space fits into.  All the energy of that space is there, but compressed time-wise?
This is the problem: which thign does what.  Is the a soliton like compression going on?
Dang, more questions than answers.
This thing, this Longitudinal Ampere forces thing, has been stuck in my brain since the 1970's!
Arg, I know there is something in there, something significant.
Understanding the how and why of this could give a whole new level of understanding the interactions of energy and matter.
And we would get our flying cars. dammit.