User Takumi Murayama - MathOverflow

Takumi Murayama

Member for 11 years
Last seen this week

GitHub
math.purdue.edu/~murayama
Purdue University, West Lafayette, IN, USA

26 Answers

Score Activity Newest

15 votes

"Noetherian" and "finitely generated" for polynomial algebras

answered May 2, 2019 at 6:37

10 votes

On Noetherian and Japanese rings

answered Feb 22, 2020 at 21:32

9 votes

Regular morphisms and formal power series

answered Feb 10, 2020 at 22:05

8 votes

Accepted

local UFD with dimension less than or equal 3 is catenary

answered Jan 7, 2020 at 20:42

7 votes

Accepted

Looking for a simple one-dimensional noetherian domain whose regular locus is not open

answered Sep 3, 2019 at 12:52

7 votes

Accepted

Quotients of Gorenstein rings

answered Aug 2, 2021 at 4:30

6 votes

Accepted

Birational Invariants of regular surfaces

answered May 28, 2019 at 13:33

6 votes

Accepted

Bertini's type theorems over imperfect fields

answered Apr 15, 2018 at 19:30

4 votes

Accepted

Structure sheaf of affine variety consists of noetherian rings (again)

answered Apr 11, 2016 at 19:35

4 votes

Accepted

Degree Bound in Bend and Break Lemmas

answered Nov 8, 2018 at 20:58

4 votes

Accepted

Is completion of isolated singularity isolated?

answered May 23, 2019 at 2:56

4 votes

Accepted

Noetherian local ring with non-lci formal fibers

answered Apr 4 at 4:17

4 votes

Relationship between the notions of "excellent ring" and "universally catenary Nagata ring"

answered Mar 11, 2020 at 23:22

4 votes

What is Serre's condition (S_n) for sheaves?

answered May 2, 2020 at 6:10

4 votes

Accepted

Frobenius splitting for an excellent, non $F$-finite, $F$-pure hypersurface

answered May 16, 2020 at 0:12

4 votes

Accepted

Nef and pseudo-effective divisors over non algebraically closed fields

answered Jul 7, 2021 at 20:33

3 votes

Accepted

Is pseudo-rationality preserved by etale morphisms?

answered Aug 2, 2021 at 16:54

3 votes

Accepted

Proper birational morphism from a Gorenstein normal scheme to a normal local domain, with trivial higher direct images, implies Cohen-Macaulay?

answered Jul 8, 2023 at 2:12

3 votes

Accepted

Tie-Breaking Trick for Log Canonical Pairs and F-pure pairs in Positive Characteristic

answered May 8, 2019 at 2:43

3 votes

Accepted

Direct image of reflexive sheaf via finite, flat map

answered Jul 21, 2018 at 21:43

2 votes

Accepted

Conditions for a smooth scheme of finite type with trivial class group to be quasi-affine

answered Apr 29, 2016 at 15:28

2 votes

Morphisms preserving weak normality

answered Jul 31, 2018 at 17:04

2 votes

Geometric regularity for infinitely generated field extensions

answered Apr 30, 2019 at 19:00

2 votes

Accepted

Proving that a morphism between power series rings is regular

answered Nov 9, 2019 at 10:08

1 vote

Accepted

Differentiability of restricted volumes of big divisors

answered Nov 17, 2018 at 19:17

0 votes

Is weak normality stable under completion?

answered Jul 27, 2018 at 19:16