只野 誉(ただの ほまれ)

研究内容

My research interests lie in the area of Geometric Analysis. In particular, I am interested in the theory of Ricci solitons which are natural generalizations of Einstein manifolds.

  

at Santiago de Compostela (Garcia, Spain, September 2017 & September 2018)

主要論文・著書・学会発表

Peer Reviewed Research Papers and Accepted Papers

[1] H. Tadano, Gap Theorems for Compact Gradient Sasaki-Ricci Solitons, International Journal of Mathematics 26 (2015), 1540009, 17 pages.

[2] H. Tadano, A Lower Diameter Bound for Compact Domain Manifolds of Shrinking Ricci-Harmonic Solitons, Kodai Mathematical Journal 38 (2015), 302–309.

[3] H. Tadano, Some Myers Type Theorems and Hitchin-Thorpe Inequalities for Shrinking Ricci Solitons, Rendiconti del Seminario Matematico Università e Politecnico Torino 73 (2015), 183–199.

[4] H. Tadano, Gap Theorems for Ricci-Harmonic Solitons, Annals of Global Analysis and Geometry 49 (2016), 165–175.

[5] H. Tadano, Remark on a Diameter Bound for Complete Riemannian Manifolds with Positive Bakry-Émery Ricci Curvature, Differential Geometry and Its Applications 44 (2016), 136–143.

[6] H. Tadano, Remark on Harnack Inequalities for the Porous Medium Equation on Riemannian Manifolds, Rendiconti del Seminario Matematico Università e Politecnico Torino 74 (2016), 309–328.

[7] H. Tadano, An Upper Diameter Bound for Compact Ricci Solitons with Application to the Hitchin-Thorpe Inequality, Journal of Mathematical Physics 58 (2017), 023503, 8 pages.

[8] H. Tadano, Some Ambrose- and Galloway-Type Theorems via Bakry-Émery and Modified Ricci Curvatures, Pacific Journal of Mathematics 294 (2018), 213–231.

[9] H. Tadano, An Upper Diameter Bound for Compact Ricci Solitons with Application to the Hitchin-Thorpe Inequality. II, Journal of Mathematical Physics 59 (2018), 043507, 3 pages.

[10] H. Tadano, Some Myers Type Theorems and Hitchin-Thorpe Inequalities for Shrinking Ricci Solitons, II, Rendiconti del Seminario Matematico Università e Politecnico Torino 77 (2019), 83-111.

[11] H. Tadano, Remark on a Lower Diameter Bound for Compact Shrinking Ricci Solitons, Differential Geometry and Its Applications 66 (2019), 231–241.

New!! [12] H. Tadano, Some Cheeger-Gromov-Taylor Type Compactness Theorems via m-Bakry-Émery and m-Modified Ricci Curvatures, Nonlinear Analysis 199 (2020), 112045.

Preprints

[1] H. Tadano, Diameter Bounds, Gap Theorems, and Hitchin-Thorpe Inequalities for Compact Quasi-Einstein Manifolds, Preprint, 2015.

[2] H. Tadano, Some Compactness Theorems via m-Bakry-Émery and m-Modified Ricci Curvatures with Negative m, Preprint, 2016.

[3] H. Tadano, Geometry of Gradient Sasaki-Ricci Solitons, Preprint, 2018.

[4] H. Tadano, Some Cheeger-Gromov-Taylor Type Theorems for Finsler Manifolds, Preprint, 2018.

[5] H. Tadano, Some New Compactness Theorems via m-Bakry-Émery and m-Modified Ricci Curvatures, Preprint, 2018.

[6] H. Tadano, Ambrose and Calabi-Type Theorems via m-Bakry-Émery and m-Modified Ricci Curvatures, Preprint, 2020.

[7] H. Tadano, Boju–Funar Type Theorems via m-Bakry-Émery and m-Modified Ricci Curvatures, Preprint, 2020.

[8] H. Tadano, m-Bakry-Émery Ricci Curvatures, Riccati Inequalities, and Bounded Diameters, Preprint, 2020.

 

at Stare Miasto in Warsaw and Krakow (Warsaw & Krakow, Poland, July 2018)

Invited Talks (International)

[1] H. Tadano, Some Myers Type Theorems and Hitchin-Thorpe Inequalities for Shrinking Ricci Solitons, Seminar on Differential Geometry, Academia Sinica (Taiwan), April 18, 2016.

[2] H. Tadano, Some Myers type Theorems and Hitchin-Thorpe Inequalities for Shrinking Ricci Solitons, Geometry Seminar at University of Santiago de Compostela (Spain), June 2, 2016.

[3] H. Tadano, Some Myers Type Theorems and Hitchin-Thorpe Inequalities for Shrinking Ricci Solitons, Geometric Analysis on Riemannian and Metric Spaces, Kyoto University (Japan), September 6, 2016.

[4] H. Tadano, Some Cheeger-Gromov-Taylor Type Compactness Theorems for Ricci Solitons, Seminar on Differential Geometry, Academia Sinica (Taiwan), December 1, 2016.

[5] H. Tadano, Some Cheeger-Gromov-Taylor Type Compactness Theorems for Ricci Solitons, Geometry Seminar at Chonnam National University (South Korea), April 25, 2017.

[6] H. Tadano, Some Myers Type Theorems for Ricci Solitons, On Geometry and Several Complex Variables, Academia Sinica (Taiwan), July 3, 2017.

[7]  H. Tadano, Some Compactness Theorems for Complete Ricci Solitons, Analytical Problems in Conformal Geometry and Applications, University of Regensburg (Germany), September 20, 2018.

[8] H. Tadano, Some Compactness Theorems for Transverse Ricci Solitons on Complete Sasaki Manifolds, 2019 Taipei Conference on Geometric Invariance and Partial Differential Equations, Academia Sinica (Taiwan), January 14, 2019.

[9] H. Tadano, Some Compactness Theorems for Transverse Ricci Solitons on Complete Sasaki Manifolds, Geometry and Probability 2019, Fukuoka University (Japan), February 1, 2019.

[10] H. Tadano, Some Myers-Type Theorems for Complete Ricci Solitons, Informal Geometric Analysis Seminar, University of Maryland (United States), March 12, 2019.

[11] H. Tadano, Some Bonnet–Myers Type Theorems for Transverse Ricci Solitons on Complete Sasaki Manifolds, Hayama Symposium on Complex Analysis in Several Variables XXI, Shonan Village Center (Japan), July 15, 2019.

[12] H. Tadano, Geometry of Ricci Solitons, Riemannian and Complex Geometry, Korea Institute for Advanced Study (South Korea), August 6, 2019.

[13] H. Tadano, Some Bonnet–Myers Type Theorems for Transverse Ricci Solitons on Complete Sasaki Manifolds, Riemannian and Complex Geometry, Korea Institute for Advanced Study (South Korea), August 8, 2019.

Contributed Talk (International)

[1] H. Tadano, Gap Theorems for Compact Gradient Sasaki-Ricci Solitons, Complex Geometry and Lie Groups, Torino University (Italy), June 19, 2014.

[2] H. Tadano, Gap Theorems for Compact Gradient Sasaki-Ricci Solitons, Geometry Seminar at University of Santiago de Compostela (Spain), June 26, 2014.

[3] H. Tadano, Geometry of Gradient Sasaki-Ricci Solitons, The 20th Symposium on Complex Geometry, Sugadaira Plateau (Japan), November 6, 2014.

[4] H. Tadano, Geometry of Gradient Sasaki-Ricci Solitons, Geometry Seminar at University of New Mexico (United States), November 19, 2014.

[5] H. Tadano, Diameter Bounds for Compact Quasi-Einstein Manifolds, Geometry Seminar at University of Santiago de Compostela (Spain), January 22, 2015.

[6] H. Tadano, Gradient Estimates for Porous Medium and Fast Diffusion Equations under the Ricci Flow, Workshop in Memory of Sergio Console, Torino University (Italy), February 24, 2015.

[7] H. Tadano, An Upper Diameter Bound for Compact Ricci Solitons with Application to the Hitchin-Thorpe Inequality, Geometry Seminar at University of Santiago de Compostela (Spain), March 12, 2015.

[8] H. Tadano, Ricci Solitons and Sasakian Geometry, Workshop on Almost Hermitian and Contact Geometry, Bedlewo near Poznan (Poland), October 23, 2015.

[9] H. Tadano, Some Myers Type Theorems and Hitchin-Thorpe Inequalities for Shrinking Ricci Solitons, A Differential Geometry Day in Memory of Our Colleague and Friend Sergio Console, Torino University (Italy), May 13, 2016.

[10] H. Tadano, Some Myers Type Theorems and Hitchin-Thorpe Inequalities for Shrinking Ricci Solitons, Differential Geometry and its Applications, Masaryk University (Czech Republic), July 11, 2016.

[11] H. Tadano, Cheeger-Gromov-Taylor Type Compactness Theorems via Modified Ricci Curvature, Geometry Seminar at University of Santiago de Compostela (Spain), July 27, 2016.

[12] H. Tadano, Some Myers Type Theorems and Hitchin-Thorpe Inequalities for Shrinking Ricci Solitons, Geometry Seminar at University of Buckingham (UK), January 30, 2017.

[13] H. Tadano, Diameter bounds, Gap Theorems and Hitchin-Thorpe Inequalities for Compact Quasi-Einstein Manifolds, Geometry Seminar at University of Buckingham (UK), January 31, 2017.

[14] H. Tadano, Some Cheeger-Gromov-Taylor Type Compactness Theorems for Shrinking Ricci Solitons, Differential Geometry Days, Torino University (Italy), April 5, 2017.

[15] H. Tadano, Some Cheeger-Gromov-Taylor Type Compactness Theorems for Ricci Solitons, XIXth International Conference Geometry Integrability and Quantization, Koral Hotel (Bulgaria), June 6, 2017.

[16] H. Tadano, Some Cheeger-Gromov-Taylor Type Compactness Theorems for Ricci Solitons, Differential Geometry, Bedlewo near Poznan (Poland), June 22, 2017.

[17] H. Tadano, Some Compactness Theorems via m-Bakry-Émery and m-Modified Ricci Curvatures with Negative m, Geometry Seminar at University of Santiago de Compostela (Spain), September 26, 2017.

[18] H. Tadano, Some Results on the Hitchin-Thorpe Inequality for Compact Ricci Solitons, Geometry Seminar at University of Buckingham (UK), September 29, 2017.

[19] H. Tadano, Myers-Type Theorems, Diameter Bounds, and Gap Theorems for Sasaki Manifolds, Constant Scalar Curvature Metrics in Kähler and Sasaki Geometry, Centre International de Rencontres Mathematiques (France), January 18, 2018.

[20] H. Tadano, Myers-Type Theorems, Diameter Bounds, and Gap Theorems for Sasaki Manifolds, Informal Geometry Workshop in “Paradiso”, Cogne (Italy), January 24, 2018.

[21] H. Tadano, Some Cheeger-Gromov-Taylor Type Theorems for Ricci Solitons, Workshop on Geometric Evolution Equations,University of Regensburg (Germany), March 5, 2018.

[22] H. Tadano, Some Myers-Type Theorems for Ricci Solitons, International Workshop “Geometry of Submanifolds and Integrable Systems”, Osaka City University (Japan), March 26, 2018.

[23] H. Tadano, Some Cheeger-Gromov-Taylor Type Theorems for Finsler Manifolds, New Methods in Finsler Geometry, Centro di Ricerca Matematica Ennio De Giorgi (Italy), May 22, 2018.

[24] H. Tadano, Geometry of Gradient Sasaki-Ricci Solitons, The 5th Workshop “Complex Geometry and Lie Groups”, University of Florence (Italy), June 12, 2018.

[25] H. Tadano, Some Myers Theorems for Transverse Ricci Solitons on K-Contact Manifolds, Glances@Manifolds 2018, Jagiellonian University (Poland), July 3, 2018.

[26] H. Tadano, Some Cheeger-Gromov-Taylor Type Compactness Theorems via Modified Ricci and Bakry-Émery Ricci Curvatures, Short Communications in ICM 2018, Rio de Janeiro (Brazil), August 6, 2018.

[27] H. Tadano, Some Myers-Type Theorems for Transverse Ricci Solitons on Sasaki Manifolds, 23rd Summer School on Global Analysis and Applications, Hotel Kolping (Romania), August 20, 2018.

[28] H. Tadano, Some Myers-Type Theorems for Transverse Ricci Solitons on K-Contact Manifolds, Geometry Seminar at University of Santiago de Compostela (Spain), September 11, 2018.

[29] H. Tadano, Some Compactness Theorems for Complete Ricci Solitons, The 24th Symposium on Complex Geometry, Shiinoki Cultural Complex (Japan), November 13, 2018.

[30] H. Tadano, Some Compactness Theorems in Riemannian and Finslerian Geometry, The 53rd Symposium on Finsler Geometry, Fukuoka Institute of Technology (Japan), November 17, 2018.

[31] H. Tadano, Some New Myers-Type Theorems via m-Bakry-Émery Ricci Curvature, Workshop on Geometric Analysis and Homogeneous Geometry, University of Queensland (Australia), June 27, 2019.

[32] H. Tadano, Some New Myers-Type Theorems via m-Bakry-Émery Ricci Curvature, 24th International Summer School on Global Analysis and Applications, Juraj Pales Institute (Slovakia), August 19-23, 2019.

Contributed Poster (International)

[1] H. Tadano, An Upper Diameter Bound for Compact Ricci Solitons with Applications to the Hitchin-Thorpe Inequality, Geometric Structures on Riemannian Manifolds, University of Bari Aldo Moro (Italy), June 26, 2015.

[2] H. Tadano, Diameter Bounds, Gap Theorems and Hitchin-Thorpe Inequalities for Compact Quasi-Einstein Manifolds, Differential Geometry and its Applications, Masaryk University (Czech Republic), July 14, 2016.

[3] H. Tadano, Some Myers Type Theorems for Complete Ricci Solitons, The 18th UK-Japan Winter School in Mathematics, University of College London (UK), January 4-8, 2017.

[4] H. Tadano, Diameter bounds, Gap Theorems and Hitchin-Thorpe Inequalities for Compact Quasi-Einstein Manifolds, Differential Geometry, Bedlewo near Poznan (Poland), June 19-24, 2017.

[5] H. Tadano, Some Myers Type Theorems for Complete Ricci Solitons, The Third Japanese-Spanish Workshop on Differential Geometry, Madrid (Spain), September 21, 2017.

[6] H. Tadano, Compactness Theorems, Gap Theorems, and Diameter Bounds for Sasaki Manifolds, The Fifth Franco-Japanese-Vietnamese Symposium on Singularities, Kagoshima University (Japan), October 31, 2017.

[7] H. Tadano, Diameter Bounds and Hitchin-Thorpe Inequalities for Compact Ricci Solitons, Workshop on Geometric Evolution Equations,University of Regensburg (Germany), March 5-8, 2018.

[8] H. Tadano, Geometry of Gradient Sasaki-Ricci Solitons, Conference and School: RIEMain in Contact, Cagliari (Italy), June 22, 2018.

[9] H. Tadano, Geometry of Gradient Sasaki-Ricci Solitons, New Trends and Open Problems in Geometry and Global Analysis, Schloss Rauischholzhausen (Germany), August 29, 2018.

[10] H. Tadano, Geometry of Gradient Sasaki-Ricci Solitons, XXVII International Fall Workshop on Geometry and Physics, University of Sevilla (Spain), September 4-6, 2018.

[11] H. Tadano, Some Compactness Theorems via Bakry-Émery and m-Bakry-Émery Ricci Curvatures, Analytical Problems in Conformal Geometry and Applications, University of Regensburg (Germany), September 17, 2018.

[12] H. Tadano, Some Compactness Theorems via Bakry-Émery and m-Bakry-Émery Ricci Curvatures, Variational Problems in Geometry and Mathematical Physics, UK-Japan Winter School, University of Leeds (UK), January 7-10, 2019.

[13] H. Tadano, Some Bonnet-Myers Type Theorems via Bakry-Émery and m-Bakry-Émery Ricci Curvatures, Variational Problems and the Geometry of Submanifolds, Centre International de Rencontres Mathematiques (France), May 29-31, 2019.

Selected Invited Talks (Domestic)

[1] H. Tadano, Gap Theorems for Compact Gradient Sasaki-Ricci Solitons, Geometry Seminar at Osaka University, Osaka University (Osaka), June 9, 2014.

[2] H. Tadano, Gap Theorems for Compact Gradient Sasaki-Ricci Solitons, The 61th Geometry Symposium, Meijo University (Aichi), August 25, 2014.

[3] H. Tadano, Gap Theorems for Compact Gradient Sasaki-Ricci Solitons, Geometry Seminar at Tokyo Institute of Technology, Tokyo Institute of Technology (Tokyo), October 24, 2014.

[4] H. Tadano, An Upper Diameter Bound for Compact Ricci Solitons with Applications to the Hitchin-Thorpe Inequality, The 62th Geometry Symposium, Tokyo University of Science (Tokyo), August 28, 2015.

[5] H. Tadano, Some Ambrose and Galloway Type Theorems for Ricci Solitons, Geometric Flows and Related Problems, Tokyo Institute of Technology (Tokyo), March 4, 2016.

[6] H. Tadano, Geometry of Ricci Solitons, Differential Topology Seminar, Kyoto University (Kyoto), February 9, 2017.

[7] H. Tadano, Some Cheeger-Gromov-Taylor Type Compactness Theorems for Ricci Solitons, Geometry Seminar at Tokyo Institute of Technology, Tokyo Institute of Technology (Tokyo), May 26, 2017.

[8] H. Tadano, On Myers Type Theorems for Ricci Solitons, Tambara Topology and Geometry Seminar, Tambara Institute of Mathematical Sciences, The University of Tokyo (Gunma), August 2, 2017.

[9] H. Tadano, Some Cheeger-Gromov-Taylor Type Compactness Theorems for Ricci Solitons, The 64th Geometry Symposium, Kanazawa University (Ishikawa), August 28, 2017.

[10] H. Tadano, Geometry of Ricci Solitons, Geometry Seminar of Ritsumeikan University (Shiga), February 1, 2018.

 

aOld Town in Zurich and Bern (Zurich and Bern, Switzerland, June 2019)

Staying Abroad (More than Two Weeks)

[1] June 21, 2014 — July 29, 2014, Institute of Mathematics, University of Santiago de Compostela (Santiago de Compostela, Spain)

[2] November 18, 2014 — January 4, 2015, Department of Mathematics and Statistics, University of New Mexico (New Mexico, United States)

[3] January 9, 2015 — January 31, 2015, Institute of Mathematics, University of Santiago de Compostela (Santiago de Compostela, Spain)

[4] February 28, 2015 — March 13, 2015, Institute of Mathematics, University of Santiago de Compostela (Santiago de Compostela, Spain)

[5] May 5, 2016 — July 28, 2016, Institute of Mathematics, University of Santiago de Compostela (Santiago de Compostela, Spain)

[6] March 3, 2017 — March 20, 2017, Institute of Mathematics, Academia Sinica (Taipei, Taiwan)

[7] February 20, 2018 — March 20, 2018, Institute of Differential Geometry, Leibniz Universität Hannover (Hannover, Germany)

[8] February 20, 2019 — March 15, 2019, Department of Mathematics, University of Maryland (Maryland, United States)

[9] December 13, 2019 — January 13, 2020, Institute of Mathematics, Academia Sinica (Taipei, Taiwan)

[10] February 18, 2020 — March 18, 2020, Department of Mathematics, University of Maryland (Maryland, United States)

 

aTaketomi Island in Japan (Ishigaki, Japan, June 2019)

Grants

[1] JSPS Grant-in-Aid for Young Scientists, 18K13417, April 1, 2018-March 31, 2022.

at Houtong Cat Village in Taiwan (Ruifang, Taiwan, March 2017)

Services(Referee of Journals, etc.)

[1] Calculus of Variations and Partial Differential Equations

[2] Annals of Global Analysis and Geometry

[3] Potential Analysis

[4] Kodai Mathematical Journal

     

at Taipei Zoo in Taiwan (Taipei, Taiwan, January 2020)

卒研・院生の指導内容

現在のところ卒業研究の指導は行なっておりませんが、卒業研究の前段階に位置する必修の授業「数学研究」を担当しております。この授業では受講生の皆さんと教科書輪読を行い、教科書の該当範囲を再構成した結果を発表して貰っています。大学院では理学研究科に所属し、幾何学を専攻する修士課程の学生さんの研究指導補助教員を務めております。

 

aLone Pine Koala Sanctuary in Brisbane (Brisbane, Australia, June 2019)

担当科目(年度により変動)

【平成29年度前期】
位相1演習(理学部第一部・B クラス):距離空間論・位相空間論
幾何学1 演習(理学部第一部・B クラス):曲線論・曲面論
数学概論(理学部第二部):論理と集合の基礎

【平成29年度後期】
幾何学2演習(理学部第一部・B クラス):曲面論
微分幾何学2演習(理学部第一部):多様体論
数学研究2(理学部第一部・D クラス):西川青季 著「幾何学的変分問題」(岩波書店)の輪読

【平成30年度前期】
位相1演習(理学部第一部・A、B クラス):距離空間論・位相空間論
幾何学1 演習(理学部第一部・B クラス):曲線論・曲面論
数学概論(理学部第二部):論理と集合の基礎

【平成30年度後期】
幾何学2演習(理学部第一部・B クラス):曲面論
数学研究1(理学部第一部・A クラス):國分雅敏 著「ウォーミングアップ微分幾何」(共立出版)の輪読

【平成31年度前期】
数学概論(理学部第二部):論理と集合の基礎

【平成31年度・令和元年度後期】
幾何学2演習(理学部第一部・A、B クラス):曲面論
微分幾何学2演習(理学部第一部):多様体論
数学研究2(理学部第一部・D クラス):井ノ口順一 著「はじめて学ぶリー群 線型代数から始めよう」(現代数学社)の輪読

【令和2年度前期】
幾何学1演習(理学部第一部・B クラス):ベクトル解析
数学概論(理学部第二部):論理と集合の基礎

【令和2年度後期】
幾何学2演習(理学部第一部・B クラス):曲面論
幾何学基礎演習(理学部第一部・A クラス):曲線論・曲面論
数学研究2(理学部第一部・D クラス):深谷賢治 著「電磁場とベクトル解析(現代数学への入門)」(岩波書店)の輪読

at Tour Eiffel (Paris, France, January 2019)

学部学生へのメッセージ

高等学校と大学の大きな違いは、高等学校が答えが用意された勉強をする場であるのに対して、大学は新しい学説を作りそれを育てて行く場であるという点です。大学の醍醐味は既存の学説や常識を吸収し、栄養として取り込むことで自らを育てていきながらも、それらを塗り替えることが出来るという点にあります。高等学校で体験した「答えが用意されている勉強」を良い意味で打ち砕き、模範解答があるとは限らない問題に対処できる知力を付けてください。

高校生へのメッセージ

大学や大学院は人生の哲学を作る場だと私は信じます。その舞台はキャンパスだけでなく世界です。教科書で有名な場所も実際は行ってみないと分かりません。エッフェル塔は誰でも知っているけれど、触ったことのある人はずっと少ないはずです。それに、実は最上階に日本政府から送られた賞状が飾ってあることを知っている人はもっと少ない。イスタンブールの猫を撫でたり(注:私は犬派です)、テロにあったパリのカフェで追悼のコーヒーを飲んだり、ハワイのビーチで寝そべったり。一見単なる観光に見えても感覚を研ぎ澄ませば意外な発見があります。現場を歩いて感じたこと、感触、匂い。全てが血となり肉となります。思い切り自由に。同時に深々と謙虚に。世界を相手に現場を歩き、大学生活を通じて自分だけの哲学を作ってください。あなたを支援してくれる多くの人々に感謝しながら。