The earth could have very well been created in six days. People fail to understand how time is not a constant. It varies with the concentration of gravity at the point and time it is being measured. As the universe expanded, the concentration of gravity was much higher than it is now. This would make the passage of time as measured now, seem much slower. Sure if we use our current clocks, it would be many millions of years. By the clock being used during those six days, a lot more happened in each twenty four hour day than happens in our current twenty four hour day.