Welcome to Tsujikawa Laboratory
|Shinji Tsujikawa's Lab.
|Department of Physics,
Faculty of Science,
Tokyo University of Science,
1-3 Kagurazaka, Shinjuku-ku,
Tokyo, 162-8601, Japan
No. 1, 8-th floor)
here for the access
of our group
Profile of Shinji Tsujikawa : Click here. You can also go to the personal
field : Cosmology,
papers in Tsujikawa's Lab： Click
Networks of collaborations: Click here.
Visitors: Click here.
activities: We have entered a
golden age where cosmology can be probed
by high-presicion observational data.
It is of interest to investigate
(1) The origin of
elementary particles, dark energy and dark matter
(2) The origin and evolution of
cosmological density perturbations
responsible for CMB and large scale structure.
(3) Construction of
cosmological models such as inflation based on
particle physics (string theory, quantum gravity etc).
Our main research interest is to reveal the
physical phenomena in the
early and late universes by confronting theoretical predictions with
We would like to construct viable cosmological models that are most
favoured from observations.
In particular we are working on the research topics listed below:
creations in early universe
Cosmic Microwave Background (CMB)
cosmological perturbations and large scale structure
gravity and observational & experimental constraints
In particular we place observational constraints on
the physics in
early universe (such as inflation) using recent observational data
of CMB (see figure 1).
We also try to understand the origin of dark energy that consists
of 70% of the energy density of the present Universe
(see figure 2).
1] Temparature anisotroies in CMB (WMAP, 2006)．
The black points represent observational data and
the red curve corresponds to theoretical predictions.
Inflationary cosmology predicts almost scale-invariant
spectra of density perturbations, which matches very
well with observational data of CMB anisotropies.
The components in the present Universe.
Dark Energy (74%) is an unknown energy which leads to
an accelerated expansion of the universe.
Matter (22%) is also an unknow matter which is
pressureless (this does not leads to accelerated expansion).
We only know the rest of the components in
- For a review paper on inflationary
cosmology, please see
Inflation dynamics and reheating
of Modern Physics 78, 537-589 (2006),
Bruce A. Bassett
(Capetown, South Africa), David Wands
and Shinji Tsujikawa
You can download this
Dynamics of dark energy
- For a review paper on dark energy,
Journal of Modern Physics D15, 1753-1936 (2006),
Edmund J. Copeland
(Nottingham, UK), M.
Sami (Jamia Millia Islamia, India)
You can download this paper from hep-th/0603057.