Wanderer

This Hugo was written in 1965 and I could not get into it as well as the others on the list. Two large spaceships as big as planets wreak havoc with the tides leaving Earth with a mess to clean up.  There were too many threads running thru this and with it a lot of disjointed jumping from one to the other often in a different order.  There was a hint though about the three body problem. I notice on my list that is the title of the winning book of 2015.  That one I do not have as yet.  On the inside cover there is some writing declaring the book is owned by Peter Gregory of Hull, 1969. He paid 6 shillings.