The big bang could not have started
as a mass singularity. If it did its
gravity would make it a black hole without any possibility of
expansion.

So do we take away gravity?
No. Because if we do we automtically
produce universal boudaries/an open
universe. Otherwise without gravity
the cosmology is one that violates
the No Boundary Proposal.

No gravity equals a violation of
the no boudary Proposal.

How do you like that?

So if you keep gravity and you don't
want a black hole the original matter
must be spread out. If it's spread out
it will not have a gravity so strong
as to not be able to expand/inflate.