there is lots of information of astral travel if you search online...it is supposed to be an innate ability that each of us can cultivate and master over time. and hokey, about LSD...I have read reports that say that LSD places you into the lower astral plane and not the higher astral planes...thanks for the reminder however

(I'm sure you meant it as a support to the subject

)
Anyway...I know people who have the ability naturally...many didn't even want to be doing it and it scared the crap out of them when they just awoke floating above themselves.
I think the main problem for most of us is that when we fear that it will not work, we are forcing the experiance, and fear and force and couterproductive...especially fear...
also other factors like your diet can effect your "abilities"...
you should work on meditating and developing your concentration more and astral travel should follow...thats my problem...
i can't focus...I have no attention span and my mind is like a crazy house filled with a million screaming people all at once...if I could get a sigle moment of silence I believe it would work...
I keep trying though...
and yes everyone does participate in the astral world while they are sleeping(as while as why they are awake but thats for another day)...and lucid dreaming is another "form" of this travel...again...i reccomend you do more research on the subject. there are some free online courses on some metaphisical websites you could try or books on the subject to read.... don't let people's joking or poking fun discourage you.
the brownies won't help any...marijuana doesn't make you hallucinate...(brandy i take it you don't smoke

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however there are certain "ethnogens" that are supposed to facilitate in this sort of spiritual journeying...
one called calea zacatechichi is supposed to increase our ability to lucid dream when smoked...
as well as many others which are supposed to have many different kinds of effects...
marijuana is an ethnogen as well...but not nearly as powerful or spiritually revealing as some of the 100% legal herbs that you can find on any ethnogen webite. I also reccomend you do some research into shamanism and what ehtnogen actually is...always remember that whatever you do should be done with a reverant and respectful mind however.
a good web site about ethnogens (and all mind alterring substances for that matter) is
www.erowid.org