BASE Penning Trap System (IMAGE) Johannes Gutenberg Universitaet Mainz Caption This is an image of BASE Penning trap system to measure magnetic movement of the antiproton. Credit Stefan Sellner, Fundamental Symmetries Laboratory, RIKEN, Japan Usage Restrictions This image may only be used in connection with the press release 'Riddle of matter remains unsolved: Proton and antiproton share fundamental properties', issued by Johannes Gutenberg University Mainz on Oct. 18, 2017. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.