Positronium imaging with the J-PET tomograph

Positron injected to the human body creates in about 40% cases the bound state of electron and positron, the positronium atom. We will argue that properties of positronium atoms  such as (environment modified) life time and production probability which can be obtained during a routine PET imaging may deliver information useful for the in-vivo cancer diagnosis and grading. We present our progress in both the development of the diagnosis method and detector construction. We will present also the potential of the J-PET detector to test the discrete symmetries (P, C, T, CP, CPT) in the decays of positronium atoms and report on the first experimental results.