From John: your guess is probably better than mine at this point. Sorry.
From me: Do you have access to any academic databases? I copied your phrase into a few of the engineering databases through my uni and there's a shit load of stuff.
If you want to have a look I can give you my login details...
That would rock.
Im finishing this paper up, and this is the last part.
get on msn!
Please and thanks
QUOTE
Conclusion:
So it is possible to have an unbounded operator so that its eigenvectors are inside the Hilbert space, and it is possible to have a bounded operator so that its eigenvectors are outside the Hilbert space.
Thanks to kitsune and her cool hookups.
I have solved my problem