Project/Area Number 
14204008

Research Category 
GrantinAid for Scientific Research (A)

Allocation Type  Singleyear Grants 
Section  一般 
Research Field 
General mathematics (including Probability theory/Statistical mathematics)

Research Institution  Kyoto University 
Principal Investigator 
SHIGEKAWA Ichiro Kyoto University, Graduate School of Science, Department of mathematics, Professor, 大学院・理学研究科, 教授 (00127234)

CoInvestigator(Kenkyūbuntansha) 
KUMAGAI Takashi Kyoto University, Research Institute of Mathematical Science, Associate Professor, 数理解析研究所, 助教授 (90234509)
HINO Masanori Kyoto University, Graduate School of Informatics, Associate Professor, 大学院・情報学研究科, 助教授 (40303888)
AIDA Shigeki Osaka University, Graduate School of Fundamental Engineering, Professor, 大学院・基礎工学研究科, 教授 (90222455)
OGURA Yukio Saga University, Faculty of Science, Professor, 理工学部, 教授 (00037847)
SHIRAI Tomoyuki Kyushu University, Graduate School of Science, Associate Professor, 大学院・理学研究院, 助教授 (70302932)
盛田 健彦 広島大学, 大学院・理学研究科, 教授 (00192782)
吉田 伸生 京都大学, 大学院・理学研究科, 講師 (40240303)

Project Period (FY) 
2002 – 2004

Project Status 
Completed (Fiscal Year 2004)

Budget Amount *help 
¥40,040,000 (Direct Cost: ¥30,800,000、Indirect Cost: ¥9,240,000)
Fiscal Year 2004: ¥12,220,000 (Direct Cost: ¥9,400,000、Indirect Cost: ¥2,820,000)
Fiscal Year 2003: ¥11,960,000 (Direct Cost: ¥9,200,000、Indirect Cost: ¥2,760,000)
Fiscal Year 2002: ¥15,860,000 (Direct Cost: ¥12,200,000、Indirect Cost: ¥3,660,000)

Keywords  Stochastic analysis / Brownian motion / Wiener space / logarithmic Sobolev inequality / spectral gap / Schrodinger operator / LittlewoodPaley inequality / Riemannian manifold / 半群の優評価 / Witten Laplacian / 格子スピン系 / 確立解析 / エントロピー / 交叉関係 / スカラーポテンシャル 
Research Abstract 
The main research area of the head investigator is diffusions in infinite dimension. At the same time, a research of diffusions on a Riemannian manifold is accomplished because geometric point of view is important in our research. We gave a probabilistic proof of the LittlewoodPaley inequality, the L^P norm equivalence between the gradient and the square of the generator, essential selfadjointness of a Schrodinger operator, and the spectral gap. The essential matter we used is the intertwining property between gradient and the generator. The use of Functional Analysis is crucial because it is irrelevant of the geometry of the space. In our general framework, we assume the logarithmic Sobolev inequality and the exponential integrability of the remaining term of the intertwining property. We also discussed the similar problem in a setting of Riemannian manifold with convex boundary. Further we considered a Schrodinger operator on the Wiener space of the form L+V,L beging the OrnsteinUh
… More
lenbeck operator. We gave a characterization of the generator domain and proved the essential selfadjointness and the spectral gap of the Schrodinger operator under a suitable condition of the potiential V. We also showed the LittlewoodPaley inequality for the the Schrodinger operator. Since we have a potential term, we need a modification of the standard proof. This method works for a HodgeKodaira operator on a Riemannian manifold with a potential. In this project, we have held several symposiums and gave financial support for participants. One of them is "Stochastic Analysis and related fields" that was a research project of the Research Institute of Mathematical Sciences in 2002. We invited Professors McKean, Ustunel, Rockner, etc., from abroad. The others are "Probability Summer School" in 2003,2004. We gave introductory lectures of frontier of recent research for graduated students. We could accomplish stimulating discussions. We also held every year "Stochastic Processes and related fields", which gave fruitful communication between researchers in Japan. As a sum, we held 24 symposiums during three years and invited 14 foreign researchers and produced many results. Less
