Take a moment to think of what we are being asked to consider here. The scientific community seems generally to accept that if past-directed time travel is possible, no one would be able to travel back to a time before the invention of the first time machine. If we accept that someone travelled back to around 2,000 BC, then an appropriate time machine must already have been invented at that time. Considering the rate at which technology proliferates, how likely is it that past-directed time travel has been around for 4,000 years without our having seen more evidence of it?

There never was nothing.