A simple way to describe a flat universe is to say all the energy/ dirt you shovel out of hole equals the energy/space inside the hole dug.

If you envision the Turok model even a flat universe can recycle itself when 'stuff' rushes toward itself from two different time directions.

COX does a lot of scientist panel shpws/lectures today. I thought he did a great job describing how time simulataneously is moving in the past future and now in his 'slice of a loaf of time'.