1st day of Quarknet

First off, I need to say I’m very excited to be in this group.  I have always been curious about dark matter, dark energy and the inner workings of the universe.  My first day of Quarknet consisted of a lot of loose ends being tied together: words being put to shapes and figures that I had seen (the tesseract) or actually understanding the data that was put in front of me (The Standard Model poster).  Also the clarification that the Gluon was the Strong Nuclear Force and it has most of the mass in a proton clarified a lot of things. 

Also I have always looked at time as a 4^th dimension. However the explanation that it is perpendicular the the x,y and z axes kind of blew my mind.  Trying to ‘see’ this is kind of odd.  I guess I’m trying to reconcile this. 

I guess my question revolves around how mass or energy is borrowed from the vacuum.  In my mind something has to be there to be borrowed from.  Could this material that is borrowed from some form of dark matter?   We are just able to ‘see’ it’s manifestation of it in these proposed / observable particles under these extreme conditions.