|MadSci Network: Astronomy|
The fact that antipodal (opposite direction) regions of the universe are separated by distances larger than could be traversed by light since the beginning of the universe is a well known problem with the original Hot Big-Bang model and is called the light horizon problem.
To solve it Cosmologists proposed the Inflationary model that says the universe expanded by a factor of 10 to the 50 very early on. This is allowed as only information is not allowed to travel faster than light. Since no information is carried, there is no problem with having the universe expand faster than the speed of light for a period of time.
If inflation is correct it probably will involve the existence of Higgs particles that are currently being sought by particle physicists. Some types of inflation theories also predict that the universe has `defects' (sort of like defects in a crystal structure) due to `spontaneous symmetry breaking'. A category of these hypothetical defects is represented by cosmic strings which have been invoked to explain various aspects of structure formation.
Most of this is very speculative of course because it relates to the very early universe when conditions of density and temperature were so extreme that we do not have very good physical theories for them. Things will undoubtebly evolve as cosmologists and high energy physicists keep working on the topic.
Try the links in the MadSci Library for more information on Astronomy.