German-Japanese cooperation for highest precision extended

They have done a good job, and their cooperation will be continued: After a successful review, the German-Japanese Center for Time, Constants and Fundamental Symmetries (TCFS) can start its second term. It will continue to strengthen the collaboration among German and Japanese institutes to advance most sensitive instruments for fundamental measurements in atomic and nuclear physics, antimatter and dark matter research, quantum optics and metrology. Three partners – the Max Planck Institutes for nuclear physics (MPIK) and for quantum optics (MPQ), the National Metrology Institute of Germany (PTB) and the Japanese flagship research institution RIKEN – will fund the centre in equal amounts with a total of around €7.5 million for an additional five years, starting in January 2024.

The collaboration between the teams will allow tackling forefront topics in precision measurements of time, constants of nature and tests of symmetries to find answers to the most fundamental questions in present physics. One of these questions addresses the lack of antimatter in our universe, which indicates a subtle difference between matter and antimatter that strongly contradicts our present understanding of the creation of the universe. Another question addresses the possibility of smallest changes of fundamental physical constant in time.

“The Centre is a unique platform to combine the outstanding expertise among the researchers to answer these questions of great scientific impact”, says Klaus Blaum, director at the Max-Planck Institute for Nuclear Physics (MPIK) and one of the Centre speakers, about the research cooperation.

The diverse research program will aim at the development of improved optical clocks based on atomic ions, hydrogen, nucleons and highly charges ions. In addition, the expertise among the Centre partners opens the possibility to improve measurements of fundamental physical constants, such as the electron mass, the fine structure consonant, the Rydberg constant or nuclear radii, and search for new physical phenomena such as fifth forces. To achieve the scientific goals, advanced experiments that enable measurements at highest precision will be pursued. To this end, the researchers will develop novel experimental techniques that enable measurements at highest sensitivities and smallest timescales. “Within the Centre a combination of world-leading researchers found each other, that are uniquely positioned to successfully execute the scientific aims” says Ekkehard Peik, one of the Centre speakers.

In addition, the joint efforts will enable the search for dark matter, a substance that is known to make up most of the matter in the universe, however lacks a direct detected, thus making its fundamental nature unknown. To search for dark matter advanced and novel experiments will be performed in the Centre. “Here the diverse expertise and methods of the experts within the Centre leads to expect substantial progress”, says Stefan Ulmer, Chief Scientist at RIKEN and professor at the HHU Düsseldorf, one of the Centre speakers.

In 2019 the initiative for founding the MPG-PTB-RIKEN Center came from the MPIK in order to bring together existing collaborations. Partners are the Max Planck Institutes for Nuclear Physics (Blaum and Pfeifer divisions) and for Quantum Optics (Hänsch group, Udem), the Physikalisch-Technische Bundesanstalt (PTB) with two departments and the QUEST Institute (Peik and Schmidt) as well as RIKEN with two research groups (Katori and Ulmer). The scientific activities are coordinated by the MPIK (Andreas Mooser).


Prof. Dr. Klaus Blaum,
Tel.: +49 (0)6221 516-850

Prof. Dr. Thomas Udem,
Tel.: +49 (0)89 32905-282

Dr. Ekkehard Peik,
PTB Department time and frequency
Tel.: +49 (0) 531 592-4400

Prof. Dr. Stefan Ulmer,
RIKEN Fundamental Symmetries Laboratory and HHU Düsseldorf
Tel.: +41 (0)75 411-9072

Stefan Ulmer, one of the Centre speakers, in front of the BASE experiment at CERN, that investigates investigates fundamental properties of antimatter. and is operated jointly by scientists from RIKEN, MPG and PTB. © Maximilien Brice, CERN