There's a bit of ambiance surrounding some thought that hangs in the air. And it's the weirdest thing. I'll want to envelop myself in something. I'll want to live a culture, or experience a universe I've never known.

I wrote a post about a feeling that seems similar to the one you just described. It is here.

Pretty much it's a sense of nostalgia for things that don't exist within reality. Our minds will create these abstract thoughts, or alternate realities where one can begin to picture things that don't actually exist. A powerful sense of longing will encumber one as they think of these alternate realities.

I find that subtleties/atmospheres within the environment can trigger this feeling. I can vividly see myself as another person in another place in time, culture, or dimension. It can be pretty abstract at times. However, I will have such a powerful yearning to become that person that ultimately doesn't exist. Someone had made a comment about it being a feeling known as sehnsucht;nostalgia for non-existent realities.

I think it could be common in a lot of INTPs due to our Si/Ti loop. Our Si is taking in things, and then it is feeding through our Ti to think in depth about it to create this powerful feeling.