Does rotation cause gravity? I want to ask that what causes gravity.
My opinion is that it is the rotation that causes gravity, when we see a whirlpool in water it takes anything that comes near to it in to the center of it. 
I have a doubt that is even gravity caused due to rotation of Earth. When earth rotates, it takes the atmosphere with it and that pressure is what we experience it as gravity, as it takes towards the center of the earth we assume it as a downward force. Is my assumption correct?
 A: 400 years of experimentation and theorizing have made it clear that mass causes gravity. In fact it is both mass and energy. 
Do you think non rotating bodies have no gravity? What you are imagining here comes from the fact that when things fall into a gravity well, or any other potential well they tend to orbit around (like water down the drain) before they fall in. It is not even rotation, but orbit motion you observed. So the orbit is caused by the attraction, and not the other way around.
I hope this helps.
A: I don't want to prove you that mass generates gravity. As ja72 already said there are hundreds of years of experience on that. Instead I just want to show you how weak and refutable are your arguments.

My opinion is that it is the rotation that causes gravity, when we see
  a whirlpool in water it takes anything that comes near to it in to the
  center of it.

Take a bucket filled with water. Then make a small hole at the central point of the bottom and let the water flow. Throw an ant in the water and watch it go to the center even with no whirpool.

When earth rotates, it takes the atmosphere with it and that pressure
  is what we experience it as gravity

The moon does not have atmosphere. Yet there is gravity. Even on Earth, bodies fall when they are inside a vacuum chamber.
