Research and Organization
RESCEU, Research Center for the Early Universe, was established in April 1999 by the ordinance of the former MEXT (Ministry of Education, Science, Sports and Culture), as one of the research facilities of the Graduate School of Science at the University of Tokyo. It is a successor to a more informal research organization with the same name, which was selected in 1995 by the Center-of-Excellence (COE) program of MEXT.
RESCEU performs comprehensive and worldwide research into the early Universe, aiming to answer fundamental questions that have been asked recurrently ever since the dawn of human history: “how did our Universe begin” and “how was its present structure formed”? Over the last decade, a general response towards these inquiries has been provided successfully by the standard Big Bang scenario, based on general relativity, combined with inflationary cosmology, initiated by the RESCEU’s former director Prof. Katsuhiko Sato. However, our attempts to make the scenario more detailed and concrete are still at an early stage.
In order to achieve these far-reaching objectives, the research focuses on three distinct ingredients of the Universe: baryons, dark matter, and dark energy. Baryons, though comprising only 4.5% of the cosmic energy density, are the only tangible substance among the three, and are found in a wide variety of densities, temperatures, nuclear species, and chemical compositions, depending on the time, location, and evolutionary stage of various celestial objects. The behavior of baryons tell us the nature of dark matter, which constitutes 23% of the cosmic share density and is likely to consist of some unknown elementary particles or primordial mini black holes. Behind these “material ingredients” is dark energy. Although it dominates the cosmic energy density (73%) and determines the structure and destiny of the Universe, its origin remains a total enigma and is regarded as one of the largest challenges of physics in the 21st century.
In practice, the overall research of RESCEU is conducted in eight Projects, which cover both “top down" approaches based on first-principle theories, and “bottom-up" ones using data from the world’s forefront experiments and observatories. The latter utilizes gravitational waves and neutrinos, as well as a wide range of electromagnetic frequencies. About a dozen researchers, mainly from the Department of Physics, the Department of Astronomy, and the Institute of Astronomy, are invited to join these Projects as associate RESCEU members. Furthermore, RESCUE has a visiting professor position, which can be used to invite world’s top-level researchers to stay with us.
Director, Prof. Yasushi Suto