text: When you move your arm you can feel air ? Think of different density water layers I could possibly replicate gravity with a helium balloon, candle and a clear box it all depends if helium is heavier than heat the balloon should drop as the lightest weight always goes up.
  
  if you try push a helium balloon into a lighter or heavier substance it will force back to its centre, so by having 3 different weights it should centre and create "gravity"