The "New" Alcubierre Warp Drive for Faster than Light Speed Travel (Count Me as a Skeptic)

This, from MetaFilter:

In 1994, theoretical physicist Miguel Alcubierre proposed a scheme for virtual faster than light travel using a real-world analog to the familiar science fiction trope known as "Warp Drive." The basic premise exploited certain space-time warping effects predicted by General Relativity to fold space-time, theoretically allowing a specially designed space craft to reach distant destinations effectively at FTL speeds without actually having to accelerate to light speed or beyond at all. There was, however, at least one major problem with the proposal: The math suggested it would require as much energy as the mass of the planet Jupiter to power the thing. But according to newer calculations based on a modified version of Alcubierre's original proposal, warp speed travel may now theoretically be within reach (warning: eyeball-gouging Space.com link), requiring drastically less energy than originally thought. Of course, not everyone's convinced there's anything to see here. And even so, prohibitive energy input requirements may not be the only serious challenge facing the development of real-world warp drive technology, so don't go packing your bags for that long overdue vacation to Risa just yet.

I, of course, always keep my spacekit packed and ready to go, just in case. [Note to self: make sure sunscreen has not passed expiration date since going back in time may not un-expire it.]

There are a couple of possible problems with the theory however ... just tiny ones.
For one thing, the design of the Alcubierre drive may require building another Alcubierre drive to build the first Alcubierre drive. (I think we can fix this by building them both together. If a whole bunch are needed, we build them in a circle. It's Alcubierre drives all the way down, as I always like to say.)

Then there's the supposed problem that the Alcubierre drive as proposed by NASA (yes, this comes from NASA, which is a good thing, I am sure we all agree), potentially requires creating negative energy density, and there's no known way to do that. The article -- I assume with some humor -- invents a "capacitor ring," a very fine deus ex machina. (To me this seems sort of like nit picking.)

Then there's the problem with warp drives becoming unstable when quantum mechanics is introduced. (Look, NASA's new energy model model also uses quantum equations -- albeit completely different quantum equations -- so this is surely a wash.)

Then there's the problem that you can't slow a ship with an Alcubierre drive to less than superluminal speeds because if you do particles in its wake will explode -- well, will release massive amounts of energy since they are no longer traveling faster than the speed of light, but I'm splitting atoms hairs -- destroying the ship. (Admittedly, this could be bad, which is why you don't want to sit in the front of the ship.  Just be patient and deplane when they get to you.)

Oh yeah, there's also the problem that while the NASA model scales down the amount of energy needed from vaporizing the entire planet of Jupiter to simply vaporizing a small car, and there's no known way to vaporize a small car (without blowing up the planet or otherwise). (Well, let's see here, a one megaton nuclear explosion converts 0.04655 kg of mass to energy.  The largest bomb ever built, the Tsar Bomb, had a yield of 50 megatons.  So we'd simply need a 1000 Tsar Bombs. to all blow up at once and be able to instantaneously use 100% of the energy generated. Sure that might be doable. I would not recommend building this in the United States, however, or, indeed, anywhere on Earth.)

Just so much negativity. Anyway, I guess, we might be a little skeptical.  You know, epileptic trees might be possible.