An Out of Body Experience is your consciousness being transferred beyond your physical body. So, is this proof of the spirit? The afterlife? Alternate dimensions? Alas, not quite. To trigger yourself, focus indoors and cut physically off from your awareness of the outside world.
Very rapidly, your mind begins to create new stimulus of its own. We call these thoughts. Usually imaginings are reserved for sleep, but as logical dreamers identify, it is probable to scam the body into sleep while enduring conscious of these hallucinations.
Out of body explorers have long tried to prove this by trying to acquire data from diverse locations even as in the out of body shape. Unhappily nothing truly definitive has been recorded under demonstrable circumstances. But science does not recognize coincidence or top guesses as evidence. That actually would get us nowhere in the grand scheme of things.