Depends. There's lots of reasons it shouldn't work yet it isn't forbidden by relativity. The main problem with it is that it requires negative pressure and we have no idea if it even exists. Negative pressure= negative energy=negative mass. Literally, -1 kg.

And even then, we would only be able to contract and expand spacetime to a finite extent before we run into the fact that it would require more negative pressure than the energy in the observable universe. That's impossible.