, I am entertaining your theory. If the oldest matter converts to energy when the accelerating universe expansion achieves light speed, the COBE microwave radiation images from the video are not necessarily the echo of the big bang, but actually the output of the continual process of matter dying at the farthest reaches of the universe.
Furthermore, is something at the center of the universe repelling matter (anti-gravity?) to cause this accelerating expansion toward the universe horizon? Where is our galaxy in this continuous process?
Regarding the age of the universe, by Einstein's relativity, time would slow to a crawl (by our measure) within those accelerating galaxies approaching the universe horizon. Do things happen significantly slower in our galactic neighborhood since our matter was formed and began expanding and careening toward the universe horizon in the course of billions of years? If we are accelerating as part of the expansion of the universe, would relative time affect our perception such that the actual age of our galaxy is less than 13.75 billion years?