In the scenarios which involve exciting the cesium atoms on Earth, what the heck do you do with them? I mean, sheesh, you've got a pile of cesium next to your power plant being excited to the same degree you're trying to produce thrust for maybe a really big spacecraft someday, and those excited little cesium ions are just gonna get more and more excited till something's gotta give. I guess you could have an elaborate recovery system to cool them down again and extract the energy...no, wait, you can't, because quantum entanglement means that cooling the Earthside cesium means cooling the cesium out in space. Or maybe that's OK if it's already exited the nozzle (nice way to stealth the exhaust). And if you're recovering energy in the scenario which doubles the energy, have you created a perpetual energy machine? See what I mean? This is gnarly!