This is a great thread. I'll add my two cents:
Are you familiar with Zeno's Paradox?
Say you have a line that is 1 foot long. You are able to divide this line into an infinite amount of smaller lines (0.5, 0.25, 0.1, 0.05, etc.)
Being that we are living in a four dimensional universe with time being one of the more important ones- Time itself must then have some sort of physical attribute.
If we are able to divide temporal constructs into more and more (infinitely many) smaller portions, does that not conclude that time has a beginning (and an end)?