The idea of 7 heavens

I was in a class learning Japji and the idea of God is "above" his creation came into discussion.

We talked about how the islam believe in the 7 layers of heaven.
i did a little search and found this very interesting website.
http://islam-watch.org/AliSina/7Layers.htm

You will realise how the quran is nothing but false statements of science. Does this mean Mohammad was messenger of God or liar.