Does the Universe Pulsate ??

I'm thinking we have Guth's theory at the first trillionth of a second
of the BB Have read that the universe had fast expansion then slowed
down for a long time,and now it is again inflating at an accelerating
rate. hmmmm My own concave and convex theory can help explain why this
is reality. It is the mysterious force of gravity. They use another name
for it. "dark energy" But a rose is still a rose. bert