Yes. You can die, which i don’t recommend. When we die presumably whatever our life presence is exits the body or at least that is the accepted interpretation of what happens. an out of body experience is generally associated with this so if it were fast and easy everyone would be doing it and dying from it and it would kinda take the specialness out of living in general.
I’ve achieved it under extreme duress or pain in under an hour or shortly after laying down to sleep. The exact time it took is not clear. The mind confuses these states with dreamscapes and hallucinations so it’s never completely clear how long it takes or lasts but if you are trying to do it as a project for your science class it probably won’t happen. It is an extreme condition of the body and mind often triggered by extreme trauma: physical pain, mental anguish, altered states, due to drugs, illness, etc. There are apparently people who can induce it in a controlled forensics lab and retrieve reliable information but i would not count on that being the case nor do i believe it is a trainable skill. If i were you i would be concerning myself with maintaining healthy conditions of the mind and body first, then if you should find yourself in a serene quiet remote setting with nothing but time on your hands. Practice some of the meditation techniques that have been known to induce OOBEs, and be prepared for something you can’t be prepared for haha! You may start with sleep paralysis which is anything but pleasant or you may have restless nights where you keep thinking you are awake but find you can’t affect anything in the physical world. eventually you may achieve some control over it. But trying to do it fast is completely missing the point. When an OOBE comes on fast it is not a good sign at all. Like i said it probably means you are dying.
This answer originally appeared on this Quora question on Astral Projection.