Nothingness in space

This one is for the space and science geeks. My friend David (we met on an AOL message board in the mid-90s, he was Musictopia and I was Angelynx, oh god I just admitted that) sent me a series of text messages this morning that made my head hurt. See if you guys can help:

So, it's impossible for actual nothingness to exist, right? Everything is something? Question: In the vacuum of space where large areas contain only a handful of particles far apart from each other, what is in between them? We can't say nothing, right? "Nothing" can't take up space. Right? So in a vast area of space you may only have a few particles and a lot of "???" Is it really completely empty? Nothing?


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I'm sure Wolfram Alpha can help somewhat, but I'm curious to hear people's explanations.