As i undestand it light saber is a plasma-like substance caught within containment field.
Fire is reaction of oxygen to overheating, there is no fire in no oxygen envirnment.
That containment field have absolute reliablity, we never see lightsaber turned into plasma torch, which would be the case if its energy is exposed to oxygen.
Its safe to presume that all destruction processes lightsaber cause are happening within that said containment field, where there is obviously no oxygen to fire , so lightsaber passed through obstacle just desintegrate matter(or melt, whatever) within its field.
Matter within field dont fire cause there is no oxygen there and very very quickly there is no matter as well. Matter near cut doest fire because its separated from the cuted area by that said containment field.
We never see any heroes wileding sabers sweat when activated blade was near their exposed skin , nor was there any sort of its reddening indicating high temperature.
So we can say near lightsaber temperature doesnt really change, hence the term "lightsaber", not heatlance or firepike or meltasword.Word Light doesnt communicate change in temperature.
In the first episode door melt because i think that hard metal was really hard and refuse to disentegrate exposed to lightsaber field and was slowly started to melt fueled by itself. In the rest cases matter was destroyed to quickly to start any such process.
P.S. Oh great i just wrote a post "How dos Lighsaber work", i guess thats official indoctrination into SW Geek..i mean fan
.I can safely now start to watch Big Bang Theory.
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