Forum:Portal 2 timeline help

I was wondering if its possible that portal takes place around the time of half life 2 and its episodes and not the thousand or so years after that was implied, during half life most of humanity was killed and the rest (not counting rebels) were rounded up into cities, which were likely high populaton centers such as new york, bejing and ect(aka not idaho). while i beleive the combine would have definetly have used aperatures portal technology its possible that the facility simply slipped their mind, or they found out about something MUCH more important on the borealis and focussed their efforts on finding it.