Relativity says that no particle can go faster than c, but that does not imply the universe can't expand faster than c. Here's why:

The universe is a space, like a blank sheet of paper, which can hold particles. The paper itself is free to expand. If the entire sheet is expanding uniformly (think: anything you draw on the paper just gets bigger), then clearly the "velocity" between two points is proportional to the distance between them. For our universe, v = H*d, where H is the Hubble constant. If d is large enough, the "velocity" might exceed c. But this does not violate relativity because in any little patch of the universe the speed limit remains c.

If space were not expanding, the most distant object we could see would now be about 14 billion light-years away from us, the distance light could have traveled in the 14 billion years since the big bang. But because the universe is expanding, the space traversed by a photon expands behind it during the voyage. Consequently, the current distance to the most distant object we can see is about three times farther, or 46 billion light-years.

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