This kind of pdf is what you get when your genius startup doesn't have a single engineer with half a brain and everybody does enough coke to believe you can beat physics with sheer enthusiasm.
That, or it is calculated fraud.
The low temperature of space is mentioned to trick non-critical people into thinking "wow smart, basically free cooling", when it is anything but. I am all for the idea of putting money into researching the topics needed to get those things going, but misleading investors like that is plainly wrong.