3. Dark Matter
With trillions of galaxies in space, their combined weight seems to be mind-boggling. But apparently, physicists think that the universe is far too light. To make their calculations work, scientists need to “create” a new type of matter that make up the bulk of the universe. Dark matters would explain many things we observe in the universe, including orbital and rotational speeds of each galaxy in clusters. Perhaps, dark matter is a great indicator on how little we know about the universe that we unashamedly made up a fictional object.