What is the initial force of universe expansion?

[Ranku]

When the universe started expanding at the big bang, was it mainly driven by the force of the big bang ? Does dark energy start to play the major role in driving the expansion only when it is accelerating?

(I would prefer to have this question answered by a PF Science Advisor or someone who actually knows about it.)

 

[Naty1]

try this thread, currently active:
https://www.physicsforums.com/showthread.php?t=318568

but some of the earlier posts are plainly wrong...try starting with post #6 from Wallace, a Science Advisor...