The fourth state of matter is Plasma.The existence of plasma was first discovered by Sir William Crookes in 1879 using an assembly that is today known as a “Crookes tube”, an experimental electrical discharge tube in which air is ionized by the application of a high voltage through a voltage coil.
The fifth state of matter is BEC (Bose-Einstein Condensate).It was discovered in 1924–25 by Satyendra Nath Bose and Albert Einstein . A Bose–Einstein condensate is a state of matter formed by bosons cooled to temperatures very near to absolute zero (0 kelvin or -273.15°C). Under such supercooled conditions, a large fraction of the atoms collapse into the lowest quantum state, at which point quantum effects become apparent on a macroscopic scale.