## Seminar information archive

#### thesis presentations

13:00-14:15   Online
Kentaro Kameoka (Graduate School of Mathematical Sciences University of Tokyo)
Studies on semiclassical analysis and resonance theory
[ Reference URL ]
https://forms.gle/bdsntP4pZ4TMaehF9

#### thesis presentations

13:00-14:15   Online
Teppei Takamatsu (Graduate School of Mathematical Sciences University of Tokyo)
On the arithmetic finiteness of irreducible symplectic varieties
[ Reference URL ]
https://forms.gle/bdsntP4pZ4TMaehF9

#### thesis presentations

11:00-12:15   Online
Yujiro Takeishi (Graduate School of Mathematical Sciences University of Tokyo)
Optimal decay estimates for Schrödinger heat semigroups with inverse square potential in Lorentz spaces
[ Reference URL ]
https://forms.gle/bdsntP4pZ4TMaehF9

#### thesis presentations

11:00-12:15   Online
Kengo Takei (Graduate School of Mathematical Sciences University of Tokyo)
Some asymptotic problems for systems of Hamilton-Jacobi-Bellman equations
[ Reference URL ]
https://forms.gle/bdsntP4pZ4TMaehF9

#### thesis presentations

9:15-10:30   Online
Shota Fukushima (Graduate School of Mathematical Sciences University of Tokyo)
Microlocal construction and analysis of the Schrödinger propagators on manifolds
[ Reference URL ]
https://forms.gle/bdsntP4pZ4TMaehF9

#### thesis presentations

11:00-12:15   Online
Yuki Yamamoto (Graduate School of Mathematical Sciences University of Tokyo)
On the restrictions of supercuspidal representations for inner forms of GL_N
[ Reference URL ]
https://forms.gle/bdsntP4pZ4TMaehF9

### 2022/01/27

#### Information Mathematics Seminar

16:50-18:35   Online
Yusuke Aikawa (Information Technology R&D Center, Mitsubishi Electric Co.)
Recent development of post-quantum cryptography from supersingular elliptic curves (Japanese)
[ Abstract ]
Explanation on recent development of post-quantum cryptography from supersingular elliptic curves
[ Reference URL ]

#### thesis presentations

13:00-14:15   Online
Masaru Miyashita (Graduate School of Mathematical Sciences University of Tokyo)
Some new approaches to the finite element method for digital twins of plasma
[ Reference URL ]
https://forms.gle/bdsntP4pZ4TMaehF9

#### thesis presentations

13:00-14:15   Online
Keiichi Maeta (Graduate School of Mathematical Sciences University of Tokyo)
On the existence problem of compact Clifford-Klein forms of indecomposable pseudo-Riemannian symmetric spaces with signature (n, 2)
[ Reference URL ]
https://forms.gle/bdsntP4pZ4TMaehF9

#### thesis presentations

9:15-10:30   Online
Nobuo Iida (Graduate School of Mathematical Sciences University of Tokyo)
A stable homotopy version of monopole contact invariant
[ Reference URL ]
https://forms.gle/bdsntP4pZ4TMaehF9

#### thesis presentations

11:00-12:15   Online
Jun Okamoto (Graduate School of Mathematical Sciences University of Tokyo)
Convergence of some non-convex energies under various topology
[ Reference URL ]
https://forms.gle/bdsntP4pZ4TMaehF9

#### thesis presentations

11:00-12:15   Online
Yasuhiro Oki (Graduate School of Mathematical Sciences University of Tokyo)
On the connected components of Shimura varieties for CM unitary groups in odd variables

[ Reference URL ]
https://forms.gle/bdsntP4pZ4TMaehF9

#### thesis presentations

13:00-14:15   Online
Tatsuro Kawakami (Graduate School of Mathematical Sciences University of Tokyo)
Studies on the Bogomolov-Sommese vanishing theorem and Du Val del Pezzo surfaces in positive characteristic
[ Reference URL ]
https://forms.gle/bdsntP4pZ4TMaehF9

#### thesis presentations

9:15-10:30   Online
Cyuyou Ko (Graduate School of Mathematical Sciences University of Tokyo)
On the Helmholtz decomposition of vector fields with bounded mean oscillation in various domains
[ Reference URL ]
https://forms.gle/bdsntP4pZ4TMaehF9

#### thesis presentations

11:00-12:15   Online
Masatoshi Goda (Graduate School of Mathematical Sciences University of Tokyo)
Statistical inference for Hawkes processes
[ Reference URL ]
https://forms.gle/bdsntP4pZ4TMaehF9

#### thesis presentations

14:45-16:00   Online
Yusuke Sato (Graduate School of Mathematical Sciences University of Tokyo)
Multidimensional continued fractions and Fujiki-Oka resolutions of cyclic quotient singularities
[ Reference URL ]
https://forms.gle/bdsntP4pZ4TMaehF9

#### thesis presentations

11:00-12:15   Online
Taketo Sano (Graduate School of Mathematical Sciences University of Tokyo)
On functoriality and spatial refinements of Khovanov homology and its variants
[ Reference URL ]
https://forms.gle/bdsntP4pZ4TMaehF9

#### thesis presentations

14:45-16:00   Online
Hiroshi Takase (Graduate School of Mathematical Sciences University of Tokyo)
Inverse problems for hyperbolic partial differential equations with time-dependent coefficients
[ Reference URL ]
https://forms.gle/bdsntP4pZ4TMaehF9

#### thesis presentations

14:45-16:00   Online
Mayuko Yamashita (RIMS, Kyoto University)
Differential models for the Anderson dual to bordism theories and invertible QFT’s
[ Reference URL ]
https://forms.gle/bdsntP4pZ4TMaehF9

### 2022/01/25

#### Tuesday Seminar on Topology

17:00-18:00   Online
Pre-registration required. See our seminar webpage.
Xiaobing Sheng (The Univesity of Tokyo)
Some obstructions on subgroups of the Brin-Thompson group $2V$ (ENGLISH)
[ Abstract ]
Motivated by Burillo, Cleary and Röver's summary of the obstruction for subgroups of Thompson's group $V$, we investigate the higher dimensional version, the group $2V$ and found out that they have similar obstructions on torsion subgroups and certain Baumslag-Solitar groups.
[ Reference URL ]
https://park.itc.u-tokyo.ac.jp/MSF/topology/TuesdaySeminar/index_e.html

### 2022/01/24

#### Seminar on Geometric Complex Analysis

10:30-12:00   Room #128 (Graduate School of Math. Sci. Bldg.)
Junjiro Noguchi (The University of Tokyo)
Analytic Ax-Schanuel Theorem for semi-abelian varieties and Nevanlinna theory (Japanese)
[ Abstract ]
The present study is motivated by $\textit{Schanuel Conjecture}$, which in particular implies the algebraic independence of $e$ and $\pi$. Our aim is to explore, as a transcendental functional analogue of Schanuel Conjecture, the value distribution theory (Nevanlinna theory) of the entire curve $\widehat{\mathrm{ex}}_A f:=(\exp_Af,f):\mathbf{C} \to A \times \mathrm{Lie}(A)$ associated with an entire curve $f: \mathbf{C} \to \mathrm{Lie}(A)$, where $\exp_A:\mathrm{Lie}(A)\to A$ is an exponential map of a semi-abelian variety $A$.

We firstly give a Nevanlinna theoretic proof to the $\textit{analytic Ax-Schanuel Theorem}$ for semi-abelian varieties, which was proved by J. Ax 1972 in the case of formal power series $\mathbf{C}[[t]]$ (Ax-Schanuel Theorem). We assume some non-degeneracy condition for $f$ such that in the case of $A=(\mathbf{C}^*)^n$ and $\mathrm{Lie}((\mathbf{C}^*)^n)=\mathbf{C}^n$, the elements of the vector-valued function $f(z)-f(0)$ are $\mathbf{Q}$-linearly independent. Then by the method of Nevanlinna theory (the Log Bloch-Ochiai Theorem), we prove that $\mathrm{tr.deg}_\mathbf{C}\, \widehat{\mathrm{ex}}_A f \geq n+ 1.$

Secondly, we prove a $\textit{Second Main Theorem}$ for $\widehat{\mathrm{ex}}_A f$ and an algebraic divisor $D$ on $A \times \mathrm{Lie}(A)$ with compactifications $\bar D \subset \bar A \times \overline{\mathrm{Lie}(A)}$ such that
$T_{\widehat{\mathrm{ex}}_Af}(r, L({\bar D})) \leq N_1 (r, (\widehat{\mathrm{ex}}_A f)^* D)+ \varepsilon T_{\exp_Af}(r)+O(\log r) ~~ ||_\varepsilon.$
We will also deal with the intersections of $\widehat{\mathrm{ex}}_Af$ with higher codimensional algebraic cycles of $A \times \mathrm{Lie}(A)$ as well as the case of higher jets.
[ Reference URL ]
https://u-tokyo-ac-jp.zoom.us/meeting/register/tJ0vcu2rrDIqG9Rv5AT0Mpi37urIkJ1IRldB

### 2022/01/21

#### Colloquium

15:30-16:30   Online
Registration is closed (12:00, January 21).
Yoshiko Ogata (Graduate School of Mathematical Sciences, The University of Tokyo)
Classification of gapped ground state phases in quantum spin systems (JAPANESE)

#### Tokyo-Nagoya Algebra Seminar

16:45-18:15   Online
Please see the URL below for details on the online seminar.
Haruhisa Enomoto (Osaka Prefecture University)
Exact-categorical properties of subcategories of abelian categories 2 (Japanese)
[ Abstract ]
Quillen's exact category is a powerful framework for studying extension-closed subcategories of abelian categories, and provides many interesting questions on such subcategories.
In the first talk, I will explain the basics of some properties and invariants of exact categories (e.g. the Jordan-Holder property, simple objects, and Grothendieck monoid).
In the second talk, I will give some results and questions about particular classes of exact categories arising in the representation theory of algebras (e.g. torsion(-free) classes over path algebras and preprojective algebras).
If time permits, I will discuss questions of whether these results can be generalized to extriangulated categories (extension-closed subcategories of triangulated categories).
[ Reference URL ]
http://www.math.nagoya-u.ac.jp/~aaron.chan/TNAseminar.html

### 2022/01/20

#### Seminar on Probability and Statistics

15:00-16:10   Room # (Graduate School of Math. Sci. Bldg.)
Yoshimasa Uematsu (-)
-
[ Reference URL ]