The third heaven is the dome or firmament, which is a sea of glass. It's a rigid crystalline sphere on the edge of space which formed in response to the creation of gravity on the second day.
The Third Heaven
The Three Heavens
Given that the apostle Paul specifically refers to something called the third heaven it's not a stretch to conclude that there must also be a first and a second heaven. We need to know what they are.
Young Earth Creationism (YEC)
The fundamental thing which sets Matty's Paradigm apart is gravity. The Bible has an extensively developed doctrine of gravity which causes a phenomenon called gravitational time dilation (GTD).
February 16th
The Apostle Paul refers to the third heaven in which case, logically, there must also be a first and second heaven. If you believe that Earth orbits a sun which is adrift in an infinite universe, you don't have a third heaven.