I always thought a lightsaber was bent light ... now hear me out ,yes light cant be stopped but it can be bent we know that light bends when things like planets come into the equation so imagine a technology so advanced that the handle has not only a really powerful laser but a really powerful gravitational field that shot the laser out and bent it back 180deg into a defused lens or maybe a ''light belt'' type situation kind of like a belt saw but with light, I know this sounds utterly ridiculous today but imagine if you went back 200 years and told people in the future 400 people will sit in a tube and fly across the planet in less than a day, you would be put on a witch pursuit thing.,(reply>), no its an advanced field it only manipulates the light we are talking about technology beyond comprehension less than 100 years ago we as a species only thought magnets could repel or attract until the brainbox Walther Meissner discovered quantum levitation  now we have Maglev technology.,(reply>), So, flick on your lightsaber and all the atmosphere (and you, and anything loose) goes to feed the black hole you just created.