I'm reading a book by Hawking and Penrose. I'm afraid it is a bit beyound me; but, I am getting the jist or is it jest of their thoughts, I think. In the book Hawking memtioned the Super Gravity Theory. I've run across it before but don't know what it is. Can someone briefly and basically explain it to me? One of the other of the many things I'm not sure about that is mentioned both in the book and here in this forum in other threads in "The Metric." Can someone define the metric again briefly and basically to me?