| Project/Area Number |
09640088
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Geometry
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| Research Institution | Saitama University |
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Principal Investigator |
MIZUTANI Tadayoshi Saitama University, Dept.of Math., Professor, 理学部, 教授 (20080492)
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| Co-Investigator(Kenkyū-buntansha) |
FUKUI Toshizumi Saitama Univ., Dept.of Math., Associate Professor, 理学部, 助教授 (90218892)
SAKURAI Tsutomu Saitama Univ., Dept.of Math., Associate Professor, 理学部, 助教授 (40187084)
NAGASE Masayoshi Saitama Univ., Dept.of Math., Professor, 理学部, 教授 (30175509)
SAKAMOTO Kunio Saitama Univ., Dept.of Math., Professor, 理学部, 教授 (70089829)
OKUMURA Masafumi Saitama Univ., Dept.of Math., Professor, 理学部, 教授 (60016053)
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| Project Period (FY) |
1997 – 1998
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| Project Status |
Completed (Fiscal Year 1998)
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| Budget Amount *help |
¥2,800,000 (Direct Cost: ¥2,800,000)
Fiscal Year 1998: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 1997: ¥1,800,000 (Direct Cost: ¥1,800,000)
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| Keywords | Poisson manifold / contact structure / Poisson cohomology / Schouten bracket / generalized divergence / symplectic foliation / leaf invariant / Dirac manifold / Hirsch foliation |
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| Research Abstract |
In the second year of the term of the project, we continued to investigate the prop- erties of the plane field which a 2-vector pi defines. A typical example of such plane field is the tangentially symplectic foliation associated with a Poisson structure. In the course of investigation, we obtained the following new insight. (1) In the first year, we showed ; when dim M = 2kappa + 1, if [pi, pi^<kappa>]<double plus> 0, pi defines a contact plane field. This time we have proved the existence of a connection of M such that Divpi (w.r.t. this connection) is a Reel) vector field of the contact structure. (2) If pi defines a (regular) Poisson sturcture, Divpi is a Poisson 1-cocycle and is the image of a modular class (= h_1 in the usual notation of characteristic classes) of the associated folation.
This result suggest the possibility of the definition of characteristic classes of singular foliations in terms of Poisson structures in some cases. As a first attempt in this direction, we picked up the left in variant Poisson structures of Lie groups and tried. to descripe the 3-dimensional leaf invarinat (h_3). In a. different direction of singular objects, we studied Dirac structure on manifoIds. A little more time is needed for us to unite these studies arid obtain adenite results.
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