Research Experience
-
1999-Now
Waseda University, Professor
-
1993-1999
Waseda University, Associate Professor
-
1989-1993
Yokohama City University, Research Assistant
-
1987-1989
Waseda University, Research Assistant
Details of a Researcher
Updated on 2025/07/25
Waseda University, Professor
Waseda University, Associate Professor
Yokohama City University, Research Assistant
Waseda University, Research Assistant
日本数学会 代数学分科会運営委員
日本数学会
Algebraic Geometry
The classification of orbits by a natural action of certain reductive linear groups
H. Kaji, O. Yasukura
Yokohama Math. J. 53 39 - 61 2006 [Refereed]
Projective geometry of Freudenthal's varieties of certain type
H Kaji, O Yasukura
MICHIGAN MATHEMATICAL JOURNAL 52 ( 3 ) 515 - 542 2004 [Refereed]
Adjoint varieties and their secant varieties
H Kaji, M Ohno, O Yasukura
INDAGATIONES MATHEMATICAE-NEW SERIES 10 ( 1 ) 45 - 57 1999.03 [Refereed]
Homogeneous projective varieties with degenerate secants
H Kaji
TRANSACTIONS OF THE AMERICAN MATHEMATICAL SOCIETY 351 ( 2 ) 533 - 545 1999.02 [Refereed]
On the inseparable degrees of the Gauss map and the projection of the conormal variety to the dual of higher order for space curves
H KAJI
MATHEMATISCHE ANNALEN 292 ( 3 ) 529 - 532 1992.03 [Refereed]
ON THE INSEPARABLE DEGREE OF THE GAUSS MAP OF HIGHER-ORDER FOR SPACE CURVES
M HOMMA, H KAJI
PROCEEDINGS OF THE JAPAN ACADEMY SERIES A-MATHEMATICAL SCIENCES 68 ( 1 ) 11 - 14 1992.01 [Refereed]
Strangeness of higher order for space curves
H KAJI
COMMUNICATIONS IN ALGEBRA 20 ( 6 ) 1535 - 1548 1992 [Refereed]
ON THE GAUSS MAPS OF SPACE-CURVES IN CHARACTERISTIC-P .2.
H KAJI
COMPOSITIO MATHEMATICA 78 ( 3 ) 261 - 269 1991.06 [Refereed]
On the Gauss maps of space curves in characteristic p
H KAJI
COMPOSITIO MATHEMATICA 70 ( 2 ) 177 - 197 1989.05 [Refereed]
ON THE TANGENTIALLY DEGENERATE CURVES
H KAJI
JOURNAL OF THE LONDON MATHEMATICAL SOCIETY-SECOND SERIES 33 430 - 440 1986.06 [Refereed]
On the normal bundles of rational space curves
H KAJI
MATHEMATISCHE ANNALEN 273 ( 1 ) 163 - 176 1985 [Refereed]
Higher Gauss maps of Veronese varieties—a generalization of Boole's formula and degree bounds for higher Gauss map images
KAJI, Hajime
Comm. Algebra 46 ( 9 ) 4064 - 4078 2018 [Refereed]
Authorship:Lead author
エンピツ片手にテキストを読もう[ブックガイド]代数
楫 元
数学セミナー/日本評論社 42 ( 8 ) 34 - 35 2003.08
On the duals of Segre varieties
H Kaji
GEOMETRIAE DEDICATA 99 ( 1 ) 221 - 229 2003.06 [Refereed]
Outside In (Delle Maxwell, Silvio Levy, Tamara Munzner監督; Minnesota Geometry Center制作)
楫 元
数学セミナー/日本評論社 39 ( 9 ) 85 - 85 2000.09
Tangent loci and certain linear sections of adjoint varieties
H Kaji, O Yasukura
NAGOYA MATHEMATICAL JOURNAL 158 63 - 72 2000.06 [Refereed]
Secant varieties of adjoint varieties: Orbit decomposition
H Kaji, O Yasukura
JOURNAL OF ALGEBRA 227 ( 1 ) 26 - 44 2000.05 [Refereed]
アレフゼロ・ホテル?無限ホテル業界の軌跡?
楫 元
数学セミナー/日本評論社 38 ( 9 ) 27 - 31 1999.08
Secant varieties of adjoint varieties
H.Kaji
Matem?tica Contempor?nea 14 75 - 87 1998 [Refereed]
On the generic injectivity of the Gauss map in positive characteristic
H Kaji, A Noma
JOURNAL FUR DIE REINE UND ANGEWANDTE MATHEMATIK 482 215 - 224 1997 [Refereed]
標数pの世界
楫 元
数理科学/サイエンス社 369 1994.03
On the space curves with the same image under the Gauss map
H KAJI
MANUSCRIPTA MATHEMATICA 80 ( 3 ) 249 - 258 1993.09 [Refereed]
On the space curves with the same dual variety
H KAJI
JOURNAL FUR DIE REINE UND ANGEWANDTE MATHEMATIK 437 1 - 11 1993 [Refereed]
Characterization of space curves with inseparable Gauss maps in extremal cases
H KAJI
ARCHIV DER MATHEMATIK 58 ( 6 ) 539 - 546 1992.06 [Refereed]
ON THE VECTOR BUNDLES WHOSE ENDOMORPHISMS YIELD AZUMAYA ALGEBRAS OF CYCLIC TYPE
H KAJI
JOURNAL OF ALGEBRA 117 ( 2 ) 297 - 326 1988.09 [Refereed]
On tangentially non-degenerate plane curves
S. Arima, H. Kaji
Bull. Sci. Engrg. Res. Lab. Waseda Univ. 111 43 - 43 1985 [Refereed]
数学ガイダンスhyper
数学セミナー編集部
日本評論社 2005.03 ISBN: 9784535784277
工科系のための初等整数論入門?公開鍵暗号をめざして?
楫 元
培風館 2000.07 ISBN: 9784563014858
Power of Ideals
KAJI, Hajime [Invited]
Minami-Chita workshop on algebraic, arithmetic, and complex geometry
Presentation date: 2025.05
Power of Ideals
KAJI, Hajime [Invited]
CAPAG 2024 Miyazaki 65
Presentation date: 2024.12
Pieri’s Formula and Its Applications
[Invited]
Presentation date: 2024.03
Some remarks on degree formulae for 2-step flag varieties
[Invited]
Presentation date: 2023.12
Push-Forward Formula for Grassmann Bundles and Its Application
Presentation date: 2023.10
Some remarks on degree formulae for 2-step flag varieties ―やっぱり Borel-Hirzebruch は偉い!!―
[Invited]
Presentation date: 2023.09
Higher Gauss maps of Veronese varieties ―a generalization of Boole’s formula―
[Invited]
Presentation date: 2019.12
Two Results on Curves in P^3
Presentation date: 2019.11
Degree Formula for Grassmann Bundles
[Invited]
NSTS Seminar in Algebraic Geometry
Presentation date: 2019.10
Powers of Ideals
[Invited]
第二回宇都宮大学代数幾何研究集会
Presentation date: 2019.09
Degree formula for Grassmann bundles, II
[Invited]
研究集会「Arithmetic and Algebraic Geometry 2019 ---in honour of Professor Tomohide Terasoma's 60th birthday---」
Presentation date: 2019.01
Degree Formulae for Two-Step Flag Varieties
[Invited]
研究集会「第一回宇都宮大学代数幾何研究集会」
Presentation date: 2018.08
Degree formula for Grassmann bundles and its applications
[Invited]
研究集会「ベクトル束の分裂・構成・安定性とその応用」
Presentation date: 2018.06
グラスマン束の次数公式 (新証明)
[Invited]
第25回沼津改め静岡研究会
Presentation date: 2018.03
On a problem posed by Alessandro Terracini
[Invited]
第5回代数幾何学研究集会-宇部-
Presentation date: 2018.01
グラスマン束の次数公式 (新証明) とその応用
[Invited]
射影多様体の幾何とその周辺
Presentation date: 2016.10
グラスマン束の次数公式 (新証明) とその応用
楫元 [Invited]
山形代数幾何小研究集会
Presentation date: 2016.08
グラスマン束の次数公式と高次ガウス写像への応用
[Invited]
Presentation date: 2015.03
Higher Gauss maps of Veronese varieties---a generalization of Boole's formula---
KAJI, Hajime [Invited]
Mini-conference on Algebraic Geometry (National Taiwan University)
Presentation date: 2015.03
グラスマン束の次数公式(続)
[Invited]
Presentation date: 2014.09
グラスマン束の次数公式
[Invited]
Presentation date: 2014.03
Degree formula for Grassmann bundles
[Invited]
Symposium on Projective, Algebraic Varieties and Moduli 2014 (in honor of Professor Changho Keem's 60th birthday), Seoul National University (Seoul, Korea).
Presentation date: 2014.02
グラスマン束の次数公式
[Invited]
Presentation date: 2013.12
接的退化曲線について
[Invited]
Presentation date: 2013.04
A tangential trisecant lemma
[Invited]
研究集会, ALGA-2012, the 12th Meeting of the Brazilian Group in Commutative Algebra and Algebraic Geometry, IMPA (Rio de Janeiro, Brazil).
Presentation date: 2012.08
A tangential trisecant lemma
[Invited]
Presentation date: 2012.03
A tangential trisecant lemma
[Invited]
Symposium on Projective Algebraic Varieties and Moduli, Novotel Ambassador (Busan, Korea)
Presentation date: 2012.02
Homogeneous projective varieties with unique secant property
[Invited]
Presentation date: 2011.11
随伴多様体の射影幾何的魅力
[Invited]
Presentation date: 2011.03
Gauss maps in positive characteristic
[Invited]
Algebra Seminar, Seoul National University (Seoul, Korea).
Presentation date: 2010.09
Gauss maps in positive characteristic
[Invited]
研究集会, ALGA-2010, the Tenth Meeting of the Brazilian Group in Commutative Algebra and Algebraic Geometry, IMPA (Rio de Janeiro, Brazil).
Presentation date: 2010.07
Gauss maps in positive characteristic
KAJI, Hajime [Invited]
Workshop ''2010 Algebra and Geometry of Subvarieties of Projective Space (in honor of Professor Fyodor Zak on his 60th birthday),'' KAIST (Daejeon, KOREA).
Presentation date: 2010.01
Projective varieties admitting an embedding with Gauss map of rank zero
[Invited]
Presentation date: 2009.11
Any algebraic variety in positive characteristic admits a projective model with inseparable Gauss map (深澤知氏との共同講演)
日本数学会秋期総合分科会, 大阪大学.
Presentation date: 2009.09
Orbit decomposition of secant varieties of adjoint varieites
[Invited]
Presentation date: 2009.09
Gauss maps in positive characteristic
KAJI, Hajime [Invited]
Sygyzies of Projective Varieties
Presentation date: 2009.09
Projective varieties admitting an embedding with Gauss map of rank zero (深澤知氏, 古川勝久氏との共同講演),
Presentation date: 2009.09
正標数のガウス写像
楫元 [Invited]
代数学シンポジウム
Presentation date: 2009.08
The generic smoothness of the Gauss map versus the reflexivity
Presentation date: 2009.02
The generic smoothness of the Gauss map versus the reflexivity
[Invited]
Presentation date: 2008.10
Existence of a non-reflexive embedding with birational Gauss map for a projective variety
Presentation date: 2008.09
The reflexivity of a Segre product of projective varieties
Presentation date: 2008.09
Projective varieties with degenerate secant varieties
[Invited]
Presentation date: 2008.06
Existence of a nonreflexive embedding with birational Gauss map for a projective variety
[Invited]
International Conference "IV Iberoamerican Conference on Complex Geometry", (Brasil, Ouro Preto)
Presentation date: 2007.08
Projective geometry of adjoint varieties
[Invited]
Algebraic Geometry Seminar, Seoul National University (Seoul, Korea)
Presentation date: 2007.06
Projective varieties with degenerate secant varieties
[Invited]
Algebraic Geometry Seminar, Seoul National University (Seoul, Korea)
Presentation date: 2007.06
The separability of the Gauss map and the reflexivity for a projective surface
Presentation date: 2006.09
随伴多様体の射影幾何的魅力
[Invited]
研究集会「Symplectic Geometry とその周辺」, 岐阜経済大学
Presentation date: 2005.11
随伴多様体の射影幾何的魅力
[Invited]
研究集会「部分多様体の微分幾何学」, 京都大学数理解析研究所
Presentation date: 2005.06
ある種のフロイデンタール多様体の射影幾何
[Invited]
シンポジウム「代数曲線論」, 神奈川工科大学
Presentation date: 2004.12
公開鍵暗号を解読せよ!−君もスパイになれる?−
[Invited]
湘南数学セミナー, 湘南国際村センター (神奈川県三浦郡葉山町)
Presentation date: 2004.12
素数を見つけて百万長者になろう!?
[Invited]
現代数学入門市民講座, 湘南国際村センター (神奈川県三浦郡葉山町)
Presentation date: 2004.12
フロイデンタール多様体の射影幾何
[Invited]
城崎代数幾何シンポジウム
Presentation date: 2004.10
Projective geometry of Freudenthal's varieties of certain type
KAJI, Hajime [Invited]
Symposium on Algebraic Geometry at Niigata 2004
Presentation date: 2004.02
ガウス写像の非分離性に関するKleiman-Pieneの問題について
[Invited]
高知研究集会「射影多様体の幾何とその周辺」
Presentation date: 2003.08
正標数の代数多様体のガウス写像について
[Invited]
談話会、東北大学
Presentation date: 2003.06
reflexivityとGauss射の分離性に関する Kleiman-Piene の問題について
[Invited]
代数幾何学シンポジウム ---高次元多様体、正標数上の話題を中心として---
Presentation date: 2003.01
Algebras with ternary product and projective algebraic geometry (三項演算をもつ代数系と射影代数幾何)
[Invited]
城崎代数幾何シンポジウム
Presentation date: 2001.10
On the reflexivity and the Gauss maps of Segre varieties
KAJI, Hajime [Invited]
ALGA-2001, Fourth Meeting of the Brazilian Group in Commutative Algebra and Algebraic Geometry,
Presentation date: 2001.08
Projective geometry of Freudenthal varieties of certain type
KAJI, Hajime [Invited]
23o. Coloquio Brasileiro de Matematica,
Presentation date: 2001.07
A new formula in simple graded Lie algebras of contact type and its applications to Freudenthal varieties
KAJI, Hajime [Invited]
Seminario de Algebra, IMPA
Presentation date: 2001.04
Secant lines of Fredunthal manifolds
KAJI, Hajime [Invited]
Seminario de Algebra, IMPA
Presentation date: 2000.10
Normal bundles of rational space curves
KAJI, Hajime [Invited]
KIAS seminar
Presentation date: 2000.03
Secant varieties of adjoint varieties---orbit decomposition---
ミニワークショップ 「代数多様体と複素解析特異点」
Presentation date: 1999.12
Projective geometry of adjoint varieties
KAJI, Hajime [Invited]
Complex Geometry: Variteis of Low Dimensions, MFO
Presentation date: 1999.08
Certain linear sections of adjoint varieties
KAJI, Hajime [Invited]
22o. Coloquio Brasileiro de Matematica
Presentation date: 1999.07
Projective geometry of adjoint varieties
KAJI, Hajime
ALGA99, Third Meeting of the Brazilian Group in Commutative Algebra and Algebraic Geometry, UNICAMP
Presentation date: 1999.07
Secant varieties of adjoint varieties---orbit decomposition---
研究集会, 「リー群と幾何学」
Presentation date: 1998.12
Degeneration of secant varieties
研究集会, 「部分多様体と特異点のトポロジーと幾何」
Presentation date: 1998.11
Secant varieties of adjoint varieties
研究集会「School on Commutative Algebra and Projective Varieties」 (長野メルパルク)
Presentation date: 1998.03
Secant varieties of K?hler C-spaces of Boothby type
研究集会「等質空間と Hesse 構造の幾何とその周辺」 (山口大学)
Presentation date: 1997.12
Homogeneous projective varieties with degenerate secants
KAJI, Hajime
1995 AMS Summer Research Instistute on Algebraic Geometry
Presentation date: 1995.09
On the pure inseparability of the Gauss maps
日本数学会代数学分科会
Presentation date: 1993.03
On the inseparable degree of the Gauss map of higher order for space curves
日本数学会代数学分科会
Presentation date: 1991.10
Strangeness of higher order for space curves
日本数学会代数学分科会
Presentation date: 1991.10
Characterization of space curves with inseparable Gauss maps in extremal cases
日本数学会代数学分科会
Presentation date: 1990.09
On the Gauss maps of space curves in characteristic $p$
日本数学会代数学分科会
Presentation date: 1989.09
Gauss maps of space curves in characteristic $p$
KAJI, Hajime [Invited]
Projective Varieties (Trieste, Italy)
Presentation date: 1989.06
Gauss maps of space curves in characteristic $p$
都立大学研究集会 ``解析および代数多様体上の諸問題''
Presentation date: 1988.01
On the vector bundles whose endomorphisms yield quaternion algebras over a product of elliptic curves
日本数学会代数学分科会
Presentation date: 1987.10
On the space curves with separable Gauss map
日本数学会代数学分科会
Presentation date: 1987.10
On the space curves with purely inseparable Gauss map
日本数学会代数学分科会
Presentation date: 1987.10
Example of $sigma$-transition matrices defining the Horrocks-Mumford bundle
日本数学会代数学分科会
Presentation date: 1987.10
On the vector bundleds whose endomorphisms yield quaternion algebras over a product of elliptic curves
第9回可換環論シンポジウム
Presentation date: 1987.10
On the vector bundles whose endomorphisms yield Azumaya algebras of cyclic type
京都大学数理解析研究所研究集会 ``Analytic varieties および stratified space における諸問題''
Presentation date: 1986.10
Generators of Brauer groups and rational solutions of quadratic forms
KAJI, Hajime
ICM in Kyoto 1986
Presentation date: 1986.09
On the normal bundles of rational space curves
日本数学会代数学分科会
Presentation date: 1985.09
Two results on curves in P^3
KAJI, Hajime
AMS Summer Research Institute on Algebraic Geometry in Bowdoin College
Presentation date: 1985.07
On the tangentially degenerate curves
日本数学会代数学分科会
Presentation date: 1985.04
Jumping-conics of vector bundles
日本数学会代数学分科会
Presentation date: 1983.09
Projective Algebraic Geometry in Positive Characteristic
Japan Society for the Promotion of Science Grants-in-Aid for Scientific Research
Project Year :
KAJI Hajime
Projective Algebraic Geometry in Positive Characteristic
Japan Society for the Promotion of Science Grants-in-Aid for Scientific Research
Project Year :
KAJI Hajime, FUKASAWA Satoru, FURUKAWA Katsuhisa
Projective Algebraic Geometry in Positive Characteristic
Japan Society for the Promotion of Science Grants-in-Aid for Scientific Research
Project Year :
KAJI Hajime, FUKASAWA Satoru, FURUKAWA Katsuhisa
On secant varieties of projective varieties
Japan Society for the Promotion of Science Grants-in-Aid for Scientific Research
Project Year :
KAJI Hajime
Real analytic approach to the stability theory of nonlinear evolution equations
Japan Society for the Promotion of Science Grants-in-Aid for Scientific Research
Project Year :
SHIBATA Yoshihiro, YAMAZAKI Masao, KAJI Hajime, TANAKA Kazunaga, KOBAYASHI Takayuki, SHIMIZU Senjo
Research on homogeneous projective varieties by Lie algebra and algebraic geometry
Japan Society for the Promotion of Science Grants-in-Aid for Scientific Research
Project Year :
YASUKURA Osami, MAEDA Hidetoshi
Boundary conditions for gavge coupled Dirac operators and their invariants.
Japan Society for the Promotion of Science Grants-in-Aid for Scientific Research
Project Year :
KORI Toshiaki, YONIDA Gen, SUZUKI Takeru, KOSAMA Tokitake, TANAKA Kazunaga, KAJI Hajime
場の量子論の数学的研究
量子群の作用素環論的研究
代数多様体の射影空間への埋め込みに関する研究
代数多様体の射影空間への埋め込みに関する研究
An application of real aualytical wethad to nonlinear evolution eguations
Master's Thesis (Department of Pure and Applied Mathematics)
Graduate School of Fundamental Science and Engineering
2025 full year
Seminar on Algebraic Geometry B
Graduate School of Fundamental Science and Engineering
2025 fall semester
Research on Algebraic Geometry
Graduate School of Fundamental Science and Engineering
2025 full year
Seminar on Algebraic Geometry D
Graduate School of Fundamental Science and Engineering
2025 fall semester
Seminar on Algebraic Geometry C
Graduate School of Fundamental Science and Engineering
2025 spring semester
Seminar on Algebraic Geometry B
Graduate School of Fundamental Science and Engineering
2025 fall semester
Seminar on Algebraic Geometry A
Graduate School of Fundamental Science and Engineering
2025 spring semester
Research on Algebraic Geometry
Graduate School of Fundamental Science and Engineering
2025 full year
Master's Thesis (Department of Pure and Applied Mathematics)
Graduate School of Fundamental Science and Engineering
2025 full year
Seminar on Algebraic Geometry A
Graduate School of Fundamental Science and Engineering
2025 spring semester
Seminar on Algebraic Geometry D
Graduate School of Fundamental Science and Engineering
2025 fall semester
Seminar on Algebraic Geometry C
Graduate School of Fundamental Science and Engineering
2025 spring semester
Research on Algebraic Geometry
Graduate School of Fundamental Science and Engineering
2025 full year
Perspectives in Mathematical Sciences [S Grade]
School of Fundamental Science and Engineering
2025 spring semester
Perspectives in Mathematical Sciences
School of Fundamental Science and Engineering
2025 spring semester
Seminar in Mathematics A [S Grade]
School of Fundamental Science and Engineering
2025 spring semester
Seminar in Mathematics A (Summer Quarter)
School of Fundamental Science and Engineering
2025 summer quarter
Seminar in Applied Mathematics A [S Grade]
School of Fundamental Science and Engineering
2025 spring semester
Seminar in Applied Mathematics B [S Grade]
School of Fundamental Science and Engineering
2025 fall semester
Seminar in Applied Mathematics A (Summer Quarter)
School of Fundamental Science and Engineering
2025 summer quarter
Research Project Spring [S Grade]
School of Fundamental Science and Engineering
2025 spring semester
Research Project Spring (Summer Quarter)
School of Fundamental Science and Engineering
2025 summer quarter
晴ればれ岡山 代数幾何学シンポジウム
Competition, symposium, etc.
伊藤敦, 楫元,古川勝久, 渡邉究
都の西北 代数幾何学シンポジウム
Competition, symposium, etc.
網谷泰治,石川大蔵,楫元,鈴木拓,古川勝久,渡邉究
都の西北 代数幾何学シンポジウム
Competition, symposium, etc.
網谷泰治、石川大蔵、大川領、鈴木拓、永井保成、渡邉究
都の西北 代数幾何学シンポジウム
Competition, symposium, etc.
楫元、永井保成、網谷泰治、古川勝久、渡邉究、石川大蔵、鈴木拓.
代数幾何講演会 "Wind from Rio, VII"
Competition, symposium, etc.
楫元
都の西北 代数幾何学シンポジウム
Competition, symposium, etc.
楫元
代数幾何講演会 "Wind from Rio, VI"
Competition, symposium, etc.
楫元
城崎代数幾何学シンポジウム2006
Competition, symposium, etc.
加藤文元, 木村俊一, 楫元
Waseda Algebraic Geometry Mini-Symposium 2006 (\supseteq "Wind from Rio, V")
Competition, symposium, etc.
KAJI, Hajime
代数幾何講演会 "Wind from Rio, IV"
Competition, symposium, etc.
楫元
RIMS研究集会 "Algebraic Geometry and Topology"
Competition, symposium, etc.
今野一宏, 石坂瑞穂, 楫元
代数幾何講演会 “Wind from Rio, III”
Competition, symposium, etc.
楫元
代数幾何学研究集会『射影多様体/代数多様体の射影幾何3+代数曲線』
楫元,前田英敏
代数幾何講演会 “Wind from Rio, II”
Competition, symposium, etc.
楫元
Mini-Symposium on Algebraic Geometry ―wind from Rio―
Competition, symposium, etc.
KAJI, Hajime
代数幾何学研究集会『射影多様体/代数多様体の射影幾何2+特異点』
Competition, symposium, etc.
楫元
代数幾何学研究集会『射影多様体/代数多様体の射影幾何』
Competition, symposium, etc.
楫元
等質射影多様体の射影代数幾何的研究
ブラジル IMPA
Faculty of Science and Engineering Graduate School of Fundamental Science and Engineering
Waseda Research Institute for Science and Engineering Concurrent Researcher
1997
1996
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