This IMPRESS-U project is jointly funded by NSF, National Science Center of Poland, and US National Academy of Sciences. The research will be performed in a multilateral international partnership that unites the Institute for Nuclear Studies of the George Washington University (USA), Stony Brook University (USA), University of South Carolina (USA), Kharkiv Institute of Physics and Technology (KIPT, Ukraine), and National Centre for Nuclear Research (NCBJ, (Poland). US portion of the collaborative effort will be co-funded by Office of International Science and Engineering (OISE), and Division of Physics of Mathematical and Physical Sciences Directorate. The Electron-Ion Collider (EIC) under construction at Brookhaven National Laboratory (BNL) was identified by US Nuclear Science Advisory Committee as a powerful discovery machine, operating like a precision “microscope” capable of taking 3D pictures of nuclear matter at femtometer scales. By analyzing high-energy head-on collisions of electron and nuclei, it will provide access to a new frontier in nuclear physics, ensuring US leadership in both nuclear science and accelerator physics and technology. Under the proposed project, a trilateral collaboration of nuclear physicists from USA, Poland and Ukraine will develop techniques that will relate characteristics of electron-proton collisions to the internal structure of proton described in terms of elementary building blocks – quarks – and quantum interactions between them.