[1/17] The 12th “AIMR Seminar”

01/07/2025

Speaker

Dr. Sonia Mahmoudi (SUURI-COOL/Mathematical Science Group, AIMR)

Title

The theory of doubly periodic tangles: a topological study towards applications in materials science

Date

January 17 (Fri), 2025, 14:10–14:55 on Japan Time

Venue

Seminar Room, 2nd floor, AIMR Main Building

Abstract

Doubly periodic tangles (DP tangles) are complex entangled structures consisting of curves embedded in the thickened plane that can be defined as lifts of links in the thickened torus. They serve as a significant framework for analyzing and understanding the topological properties of interwoven filament systems across micro-, meso-, and macro-scales, including, but not limited to, molecular assemblies, polymer melts, fabric-like structures, and cosmic filaments.

Despite the importance of these systems, existing CAD/CAM software is largely limited to visualization of complex entangled structures. Tools for simulating their topology, predicting physical properties, and linking structure to function are still lacking, leaving a significant gap in the design of materials with targeted properties. Addressing this requires a topological study of DP tangles, which provides an important for developing such tools.

The topological classification of DP tangles is at least as hard a problem as the full classification of knots and links in three-space and is approached by constructing topological invariants. To reduce the complexity of the classification problem of DP tangles, a strategy is to consider the quotient of a DP diagram under a periodic lattice, namely a link diagram in the (flat) torus that we call a (flat) motif. This approach leads to a two-dimensional diagrammatical theory of the topological equivalence of DP tangles, which has been established in [1] on the level of motifs, generalizing works initiated by Grishanov et al. related to textiles [2,3].

In this talk, we will classify DP tangles using the well-known Jones polynomial, extended to take into account periodic boundary conditions [4]. Originally developed for classical knots and links, the Jones polynomial is a notable invariant with deep connections to statistical mechanics (via the Potts model) and quantum field theory (via Chern-Simons theory). We will show that the Jones polynomial remains an invariant for DP tangles through the introduction of new topological invariants that we will present [5,6]. These invariants appear as interesting measures to compare the topological complexity of DP tangles. Finally, we will present examples of computations of these invariants on several DP tangles, comparing them with some known numerical invariants.

  • [1] I. Diamantis, S. Lambropoulou, S. Mahmoudi, Equivalences of doubly periodic tangles, arXiv:2310.00822 (2023).
  • [2] S.A. Grishanov, V.R. Meshkov, A.V. Omel’Chenko, Kauffman-type polynomial invariants for doubly periodic structures, Journal of Knot Theory and its Ramifications, 16, (2007) 779-788.
  • [3] H.R. Morton, S.A. Grishanov, Doubly periodic textile structures, Journal of Knot Theory and its Ramifications, 18 (2009) 1597-1622.
  • [4] S. Mahmoudi, On the classification of periodic weaves and universal cover of links in thickened surfaces, Communications of the Korean Mathematical Society, 39, No. 4, (2024), 997–1025.
  • [5] I. Diamantis, S. Lambropoulou, S. Mahmoudi, Directional invariants of doubly periodic tangles, Symmetry, 16(8), (2024), 968.
  • [6] I. Diamantis, S. Lambropoulou, S. Mahmoudi, On the combinatorics of doubly periodic tangles, in preparation.

AIMR Seminars and Tea Time

We hold AIMR Seminars and Friday Tea Time as part of the initiative to promote fusion research.

Seminars are presented by AIMR researchers and visiting scientists who provide a wide range of hot topics from materials science to mathematics. The aims of the AIMR Seminar are to build up mutual understanding, communication, and discussions of each other’s research fields.

Weekly held Friday Tea Time is where AIMR researchers and staff members can relax and talk freely while drinking coffee. Expectations of stimulating conversation may arise among the researchers and leading to new research.

From 2024, active fusion research through synergistic effects from AIMR Seminars and Friday Tea Time will be promoted.

Past AIMR Seminar

11th Jan. 10, 2025 Prof. Lorenzo Di Bari (University of Pisa)
10th Dec. 13, 2024 Dr. Yuta Yoshimoto (Fujitsu Ltd.)
9th Nov. 29, 2024 Prof. Zhiqiang Mao (Pennsylvania State University, U.S.A.)
8th July 19, 2024 Dr. Shuai Wei (Aarhus University, Denmark)
7th July 5, 2024 Prof. Henning Schomerus (Lancaster University, U.K.)
6th May 10, 2024 Prof. Hidekazu Kurebayashi (University College London, U.K.)
5th May 1, 2024 Prof. Michael Hirscher (Max-Planck-Institute for Intelligent Systems, Germany)
4th Apr. 26, 2024 Prof. Konstantinos Danas (ELyTMax, CNRS-Tohoku University)
3rd Mar. 13, 2024 Prof. Ryoko Tomiyasu (Institute of Mathematics for Industry, Kyushu University)
2nd Jan. 26, 2024 Prof. Michael I. Ojovan (Imperial College London, U.K.)
1st Jan. 12, 2024 Dr. William Chuck Witt (University of Cambridge, U.K.)

About Tea Time Talk

As part of an event during Friday Tea Time, AIMR has been hosting lectures by famed researchers and the archives up to 2023 are listed below:

43rd July 21, 2023 Prof. Feral Temelli (University of Alberta, Canada)
42nd June 30, 2023 Dr. Douglas Brumley (The University of Melbourne, Australia)
41st Mar. 28, 2023 Prof. Motomu Tanaka (Physical Chemistry of Biosystems, Institute of Physical Chemistry, Heidelberg University, Germany)
40th Nov. 10, 2022 Prof. Masahiro Yoshimura (National Cheng Kung University, Taiwan)
39th June 17, 2022 Prof. Rana Mohtadi (Toyota Research Institute of North America)
38th June 17, 2022 Prof. Michael Hirscher (Max-Planck-Institute for Intelligent Systems, Germany)
37th June 3, 2022 Prof. Reiko Oda (French National Centre for Scientific Research)
36th May 28, 2021 Prof. Magda Titirici (Imperial College London, U.K.)
35th Mar. 26, 2021 Prof. Yaroslav Blanter (Kavli Institute of Nanoscience, Delft University of Technology)
34th Oct. 23, 2020 Dr. Kazuhito Tsukagoshi (PI:WPI-MANA, NIMS & AIMR)
33rd July 17, 2020 Prof. Kaoru Tamada (IMCE, Kyushu University & AIMR)
32nd Jan. 17, 2020 Prof. Miho Yamauchi (I2CNER / Kyushu University & AIMR)
31st Jan. 17, 2020 Prof. Mickaël Lallart (INSA Lyon, Université de Lyon)
30th Oct. 25, 2019 Assoc. Prof. Frédéric Gillot (Department of Solid Mechanics, Mechanical Eng. and Civil Eng., École Centrale de Lyon)
29th July 12, 2019 Prof. Qian Niu (Department of Physics, The University of Texas at Austin)
28th May 17, 2019 Prof. Damien Fabrègue (INSA Lyon, France / ELyT MaX Lab at Tohoku University)
27th Dec. 14, 2018 Prof. Yukitoshi Motome (Department of Applied Physics, The University of Tokyo, Japan)
26th July 13, 2018 Dr. Shimpei Ono (Central Research Institute of Electric Power Industry, Japan)
25th May 11, 2018 Dr. Pierre-Antoine Geslin (Mateis lab, INSA Lyon/CNRS / ELyTMaX Lab at Tohoku University / Institute for Materials Research, Tohoku University)
24th Apr. 27, 2018 Prof. Masaru Tsukada (AIMR, Tohoku University)
23rd Dec. 8, 2017 Prof. Jean-Yves Cavaillé (INSA Lyon, France / ELyT MaX Lab at Tohoku University)
22nd July 28, 2017 Prof. Nicolas Mary (INSA Lyon, France / ELyT MaX Lab at Tohoku University)
21st July 21, 2017 Prof. Gael Sebald (INSA Lyon, France / ELyT MaX at Tohoku University)
20th July 7, 2017 Prof. Arun Bansil (Northeastern University)
19th June 30, 2017 Dr. Takeshi Nakanishi (AIST-Tohoku U Mathematics for Advanced Materials Open Innovation Laboratory (MathAM-OIL))
18th June 23, 2017 Prof. Denis Arčon (Jožef Stefan Institute, Slovenia)
17th Apr. 28, 2017 Prof. Ayumi Hirano (AIMR, Tohoku University)
16th Nov. 29, 2016 Dr. David Guy Austing (National Research Council Canada, Canada)
15th Sept. 30, 2016 Prof. C. Suryanarayana (University of Central Florida, U.S.A.)
14th June 17, 2016 Prof. Tomoteru Fukumura (AIMR, Tohoku University)
13th May 13, 2016 Prof. Jean-Yves Cavaillé (ELyT MaX (Joint Lab at Tohoku University), University of Lyon, France)
12th June 26, 2015 Dr. B. Muralidharan (Indian Institute of Technology Bombay, India)
11th June 27, 2014 Prof. Michael B. Santos (The University of Oklahoma, U.S.A.)
10th Nov. 19, 2013 Dr. Pawel Hawrylak (National Research Council Canada, Canada)
9th Oct. 1, 2013 Dr. Yuan T. Lee (Nobel laureate in Chemistry, Academia Sinica of Taiwan)
8th June 28, 2013 Dr. Bjorn Mysen (Geophysical Laboratory, Carnegie Institution for Science, U.S.A.)
7th Apr. 12, 2013 Prof. Yiming Li (National Chiao Tung University, Taiwan)
6th Jan. 18, 2013 Prof. Tomasz Dietl (Polish Academy of Sciences, Poland)
5th Aug. 31, 2012 Prof. John H. Perepezko (University of Wisconsin-Madison, U.S.A.)
4th Aug. 17,2012 Prof. Alain Reza Yavari (Grenoble Institute of Technology, France)
3rd Aug. 10, 2012 Prof. Alan Lindsay Greer (University of Cambridge, U.K.)
2nd July 6, 2012 Prof. Winfried Teizer (Texas A&M University, U.S.A.)
1st May 25, 2012 Prof. Thomas P. Russell (The University of Massachusetts Amherst, U.S.A.)

Contact

Kazuto Akagi
Deputy Director, Research Support Division, AIMR

E-mail: kazuto.akagi.b5@tohoku.ac.jp