SPT and Dark Energy

Here's a link to the Smithsonian Magazine 2010 article on South Pole Telescope and Dark Energy. My take on all of this dark material is that (1) we don't know really anything about the cosmic matter we are nested and (2) why does everything have to adhere to gravity? Gravity could be a myth for all I know... how is that human levitation has been documented in many ancient texts? Are we missing something?