There is a lot of loose thinking afoot regarding the nature of infinity. I've decided to go on record with some facts:

There are just two conditions under which the Universe could be infinite in extent:

. (1) Its expansion rate must have been infinite over at least some infinitesimally brief interval of time,
or
. (2) The Universe must have been expanding over an infinite period of time.

The Big Bang theory assumes that neither of these conditions was met.

Even if the Universe were infinite in extent, it still would not follow that there must neceessatrily be duplicate copies of anything in the Universe. There could exist, for example, an infinite number of different things. There COULD be duplicate copies, but it is not necerssary that there be.