Accelerated universe expansion

It is believed that particle-antiparticle pairs spontaneously appear, and then cancel each other out. If for any reason the pair is separated before canceling each other out, than what is left is additional matter.

Could the edge of an expanding universe facilitate these particle-antiparticle pair separations by coming in between the pair? This would be the opposite of hawking radiation where a black hole losses particles through a similar process. If particle-antiparticle pair separations increase than the size of the universe would also increase. This would in turn cause the process to accelerate.

The larger the edge of the universe the more particle antiparticle pairs separate and the more mass is added to the universe. The increase in mass expands the universe which would in turn increase the boundary where separations occur. This could contribute to or cause the accelerated expansion of the universe.