piers anthony has a series called I think kirilian quest. There is no ftl and the law of physics as we know them can't be circumvented (I think its been awhile but maybe its real difficult and rarely used). Anyway all civilizations eventually realize astral projection is possible and time and space make no difference. Thing is it takes two types of people to work. People with strong auras can project and people with weak auras can be possesed. Its not a requirement but more it will work better and last longer. Anyway people with the strongest auras get jobs traveling and people with the lowest get jobs as vessels. This is how communication between societies in an intergalactic culture communicate and interact.