Filed of Research

My research area is cosmology and the large-scale structure of the universe. I'm a theorist and interested in understanding how the structure of the universe have formed throughout the history of the universe. The universe is governed by linear, quasi-nonlinear, and fully nonlinear dynamics, depending on scales of interest. Linear and quasi-nonlinear dynamics are accessible by analytical methods and fully nonlinear dynamics is appropriately depicted by numerical simulations. While analytic approaches are my primary interest, I analyze data from numerical simulations as well as data from actual observations, when necessary.

Among others, the galaxy redshift survey is one of the best way to characterize the present and mid-redshift universe. Statistical nature of the large-scale structure sheds lights on the global history of the universe. I've developed analytical methods to characterize the large-scale structure and also exploited novel statistical methods to analyze the galaxy redshift surveys. The Sloan Digital Sky Survey is the largest ongoing survey, which I'm now involved in from a theorist's standpoint.
Selected Publications

  • Correlation Function in Deep Redshift Space as a Cosmological Probe, Takahiko Matsubara, The Astrophysical Journal, 615 (2004), in press.

  • Eigenmode Analysis of Galaxy Distributions in Redshift Space, Takahiko Matsubara, Alexander S. Szalay, and Adrian C. Pope, The Astrophysical Journal, 606 (2004), pp. 1-24

  • Phase Correlations in Non-Gaussian Fields, Takahiko Matsubara, The Astrophysical Journal Letters, 591 (2003), pp. L79-L82

  • Apparent Clustering of Intermediate-redshift Galaxies as a Probe of Dark Energy, Takahiko Matsubara & Alexander S. Szalay, Physical Review Letters, 90 (2003), 021302

  • Statistics of Smoothed Cosmic Fields in Perturbation Theory I: Formulation and useful formulas in second-order perturbation theory, Takahiko Matsubara, The Astrophysical Journal, 584 (2003), pp. 1-33

  • The Correlation Function in Redshift Space: General Formula with Wide-angle Effects and Cosmological Distortions, Takahiko Matsubara, The Astrophysical Journal, 535 (2000), pp.1-23.

  • Cosmological Redshift Distortion of Correlation Functions as a Probe of the Density Parameter and the Cosmological Constant, Takahiko Matsubara & Yasushi Suto, Astrophysical Journal Letters, 470 (1996), pp.L1-L5.

  • Diagrammatic Methods in Statistics and Biasing in the Large-Scale Structure of the Universe, Takahiko Matsubara, Astrophysical Journal Supplement 101 (1995), pp.1-28.

  • Analytic Expression of the Genus in Weakly Non-Gaussian Field Induced by Gravity, Takahiko Matsubara , Astrophysical Journal Letters 434 (1994), pp.L43-L46.

  • Scale-dependence of Three-point Correlation Functions: Model Predictions and Redshift-space Comtamination, Takahiko Matsubara & Yasushi Suto , Astrophysical Journal 420 (1994), pp.497-503.