tokyo

The Super-Kamiokande neutrino detector: results will throw light on cosmological theories. Credit: ICRR, UNIV. TOKYO

The University of Tokyo has announced plans to set up a research centre to study the ‘Big Bang’ model of the origins of the Universe from both observational and theoretical perspectives.

One goal of the centre could be to explore a new and more flexible theory for solving the problems posed by the presence of free parameters in this model which has long restricted its predictive power.

Researchers from the university say their interest in the theory has been strengthened by recent findings from distant supernova explosions which suggest that the Universe entered a period of intense inflation shortly after the Big Bang, as advocated by the theory of ‘cosmological inflation’.

The centre will be set up in April within the university's department of science. It will replace the Research Centre for the Early Universe (RESCEU), a five-year project funded by the Ministry of Education, Science, Sports and Culture (Monbusho) to study the origin and evolution of the Universe.

Although RESCEU, which began in 1995, should not end until March next year, its replacement by the new research centre will be a year earlier than scheduled. This is to allow the earliest possible start to the new project, which will merge five research divisions from RESCEU with three new divisions, including one set up specifically for overseas researchers.

The centre, which will conduct research in areas such as the very early Universe, dark matter, cosmic rays and the formation and evolution of galaxies, will be part of Monbusho's ‘centre of excellence’ programme, which supports research organizations carrying out ‘highly creative scientific research’.

“An early start will allow us to take a step towards our aim to create an international base for research on the Big Bang model,” says Katsuhiko Sato, professor of theoretical astrophysics and the director of the new centre.

“We feel this is the time to give substance to the theoretical model by applying results from areas such as nuclear and particle physics as well as data obtained from the latest observations.”

According to Sato, the centre will consist of two sections: theories of the early Universe, which will take a ‘top down’ approach based on the theory of cosmological inflation developed by Guth, Linde and Steinhardt in the early 1980s, which proposes a very rapid expansion of the Universe shortly after the Big Bang; and a ‘bottom up’ approach of creating models using observational data and results obtained from experiments in particle physics.

It is hoped that the observations of neutrinos from supernova explosions, such as those by researchers from Tokyo University's Institute for Cosmic Ray Research using the Super-Kamiokande neutrino detector, will contribute to the systematic study of particles needed to understand the early Universe.

Studies of the early Universe, including research on its birth and on cosmological phase transitions, primordial nucleosynthesis, and baryogenesis (the production of protons and neutrons), based on general relativity and particle physics, will use observational data obtained from national sources, such as Monbusho's Institute of Space and Astronomical Sciences, as well as those from international sources such as the Sloan Digital Sky Survey.

“The importance of the project lies in the fact that our research will be driven by both theory and observational data. This will allow quantitative comparisons between results from observations and those from theories, and will also help to integrate research results from different fields,” says Sato.