Atheists, how did the Egyptians build the great pyramids considering that we couldn't build it today?

You are mindlessly repeating some absurd misinformed "gou pi' from a crude hoax. It took many, many workers and much time to build such large structures. We could certainly build them today, if anyone wanted to employ so many people and work all of his life at doing such a thing for no good reason. The construction has been explained, so seek the details, rather than blindly believing "The Chariots Of The Gods" that was refuted soon after it was first published. Eric van Daniken was in prison thrice for theft and fraud, so he is hardly trustworthy.