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What Was New ?
 I may attend the following meetings and conferences in the academic year
2011/2012:
 RIMS Conference 2011
Geometry of transformation groups and Combinatorics
(RIMS, Kyoto University, June 13  17, 2011)
 The 58th Topology Symposium (Tsukuba University, Aug. 8  11, 2011)
 MSJ Autumn Meeting (Shinshu University, Sept. 28  Oct. 1, 2011)
 The 38th Symposium on Transformation Groups (Hyogo Prefecture Citizens' Hall, Kobe, Nov. 1820, 2011)
 The 10th Pacific Rim Geometry Conference 2011 (Osaka City Univ. Dec. 15, Kyushu Univ. Nishijin Plaza Dec. 79, 2011)
 EACAT4 2011 (East Asian Conference on Algebraic Topology) (University of Tokyo, Dec. 59, 2011)
 Fukuoka Homotopy Theory Seminar(Fukuoka University Seminar House, Jan. 7, 8)
 Hurwitz Action (Osaka City University, Jan. 2829, 2012)
 Workshop on Intuitive Geometry (Kumamoto University, Feb. 1112, 2012)
 Knot Theory Past and Future(Waseda University, March 1718, 2012)
 MSJ Annual Meeting 2012(Tokyo Univ. Sci., March 2629, 2012)
 I uploaded the manuscript "Squeezing on a Certain Lspace"
which is to appear in the proceedings of the RIMS Conference "Transformation Groups and Surgery Theory"
 Jan 13, 2011.
 I plan to attend the following meetings and conferences in the academic year
2010/2011:
 The 57th Topology Symposium (Santa Hall, Okayama, Aug. 11  14, 2010)
 RIMS
Conference on Transformation Groups and Surgery Theory
(RIMS, Kyoto University, Aug. 30  Sept. 3, 2010)
 MSJ Autumn Meeting (Nagoya University, Sept. 22  25, 2010)
 The 37th Symposium on Transformation Groups (Kyushu University, Nov. 23  25, 2010)
 Fukuoka Homotopy Theory Seminar(Fukuoka University Seminar House, Jan. 8, 9)
 Workshop on Transformation Group Theory in Honor of Yasuhiko Kitada, Kyoto (Campus Plaza Kyoto, Feb. 12, 9:2017:00)
 Rigidity School, Nara 2010/2011(Nara Chamber of Commerce and Industry, March 58, 2011)
MSJ Spring Meeting 2011(Waseda University, March 2023, 2011) Cancelled due to the earthquake!
 I am organizing the RIMS Conference "Transformation Groups and Surgery Theory",
which will start around 2 o'clock on Aug. 30 and will end at noon on Sept. 3, 2010.
The program will be announced in early July.
If you are interested in giving a talk, please contact me.
 May 19, 2010.
 More Conferences
 There will be a conference "Topology, Geometry, Dynamics" dedicated to the 90th anniversary of the birthday of
Vladimir Rokhlin (1919  1984) from January 11th through 16th in Saint Petersburg, Russia.
I do not think I will be able to attend it.
 Nov. 6, 2009.
 I uploaded some pictures I took in Münster
here.
 June 17, 2009.
 I plan to attend the following meetings and conferences in the academic year
2009/2010:
 Geometry and Topology
(Münster, June 1  5, 2009)
 The 56th Topology Symposium (Hokkaido University, Aug. 8  11, 2009)
 RIMS
Conference on the New Development of Transformation Group Theory
(Kyoto University, Aug. 17  20, 2009)
 MSJ Autumn Meeting (Osaka University, Sept. 24  27, 2009)
 Workshop on CassonFreedman Theory (Kyoto Keihanna Plaza Hotel, Oct. 17  20, 2009)
 The 36th Symposium on Transformation Groups (Osaka, Dec. 10  12, 2009)
 I added pictures of International Openair Expressions 2004 Hiki
and pictures taken in Sapporo
to the Snapshots 2004 page.
 April 15, 2009.
 While some of my senior seminar students were studying Pick's theorem,
one of them reported on
Nukaga's theorem
which gives a method to compute the area of lattice polygons in a different way.
Here
is an English translation of a report by my students.
 February 28, 2009.
 RIMS
Conference on the New Development of Transformation Group Theory
will be held from 17 Aug. through 20 Aug. , 2009 in Kyoto.
 February 6, 2009.
 There will be a conference on Geometry and Topology
at the University of Münster, starting on June 1 and ending on June 5, 2009.
 November 7, 2008.
 The abstracts of the talks
of the 35th Symposium on Transformation Groups
are now available.
 November 7, 2008.
 I will be attending
the Topology Symposium
to be held in Kanazawa from Aug. 6 thru Aug. 9.
I will hand out an announcement
(written in Japanese) of
the 35th Symposium on Transformation Groups
there.
 August 5, 2008.
 Meetings on transformation group theory:
 Five of my senior seminar students read "Topology of Surfaces,
Knots and Manifolds" by S. C. Carlson and compiled the solutions
to the endofchapter problems as a senior thesis
[presentation pdf files:
#1
#2,
#3,
#4,
#5 (in Japanese)].
The other two students studied vector fields on surfaces and wrote
a joint thesis "Vector Fields
and Hair Whirls" [pdf for
presentation] (in Japanese).
The main result is an extension
of the PoincareHopf Theorem for continuous vector fields on a compact surface
that have only isoated singular points in the interior.
When they are almost finishing the thesis, we learned about the work of M. Morse
on general vector fields with singularities away from the boundary.
Since it was too late to incorporate the stuff into the thesis, they only
mentioned Morse's formula in a remark. I discussed Morse's formula
("the law of vector fields") with H. Kamae (one of the students), and
we now think the formula can be extended to the case where the vector field V
is allowed to have isolated singular points also on the boundary:
This is true at least when the "boundary" of V has only isolated singular points.
The idea is to consider the double DX of the manifold X (i.e. the boundary
of Xx[1,1]) and define the "double" DV of V to be equal to
V on the two copies of X and to be the obvious homotopy
on the rest. Note that we have the "boundary" of V in the middle.
Please let me know if this is already known to people.
 March 2, 2008 (modified on March 5, 2008)
"Local indices of a vector field at an isolated zero on the boundary"
(arXiv: math.GT.0803.2139)
[the 2nd versionMarch 19, 2008]
[errataupdated on March 21, 2008]
[the 3rd versionApril 3, 2008]
[the 4th versionApril 6, 2008]
 A list of meetings in Topology
 The 54th Topology Symposium (University of Aizu, Aug.69, 2007)
 MSJ Fall Meeting 2007 (Tohoku University, Sept. 2124, 2007)
 The 34th Symposium on Transformation Groups (Wakayama Municipal Auditorium, Nov. 2224, 2007)
 International Conference on Topology and its Applications 2007 at Kyoto (University of Kyoto, Dec. 37, 2007)
 4 Dimensional Topology (Hiroshima UNiversity, Jan.????, 2008)
 MSJ The Annual Meeting 2008 (Kinki University, Mar. 2326, 2008)
 I will attend the RIMS meeting
"The Theory of Transformation Groups and its Applications " (May 28  June 1, 2007).
[abstract:Assembly in Surgery, Aug. 29]
 I will talk about surgery theory at the geometry seminar of OUS
on April 20, and also on April 27, 2007, from 15:30 to 17:30.
I plan to use the same pdf file I used at Kinosaki.
 Apr. 16, 2007.
 A new book titled
"The Boy of the Sun: A study of 'In the Heat of the Sun'"
has been published in China. I have placed an order of a copy.
I am very excited and looking forward to its arrival.
 Apr. 16, 2007.
 I corrected several errors and added some ingredients to
the presentation pdf file
of the lectures at Kinosaki.
 Mar. 19, 2007.
 My senior seminar students wrote
a joint thesis "Knots and Bands"
(in Japanese). The main result is :
let M be a Moebius band in the 3space. Cut M along the center line
and obtain an annulus A. The center line of A is a trivial knot if only if
the center line of M is a trivial knot and M is half twisted.
Here is a pdf file they used for the presentation:
[pdf] (in Japanese).
 Mar. 1, 2007.
 Lewis C. Tiffany Garden Museum
in Matsue will be closed at the end of March.
I visited the museum when it was in Nagoya, and was very impressed.
When I moved to Okayama, I was very happy because the museum is rather
close to Okayama. I thought I could go there anytime, and did not visit the
museum after moving to Okayama. I will visit the museum in March.
 Feb. 27, 2007.
 I will give three 90minute lectures
(pdf)
on surgery theory at
Kinosaki School / Topology in the 60's (March 12  15, 2007).
Well, I really do not know much about the 60's, since I was an elementary/middle
school student back then.
 Jan. 18, 2007.
 Sayuri Haraguchi 
the wife of Masatake Kuranishi of Columbia University  is a daughter
of a psychologist Tsuruko Haraguchi, who is the first Japanese woman
getting a Ph.D. A documentary film of Haraguchi is being shot now.
Kuranishi and his wife will appear in the film.
See the diary of the director Etsuko Izumi which appeared
in the recent issue of
CinemaJournal magazine.
 Dec. 22, 2006.
[Official Site : http://www.sepia.dti.ne.jp/tess/]
 Two films featuring Xia Yu will be shown at the
ChinaShanghai Film Festival in Tokyo this month.
The details can be found at
the official site.
 Dec. 5, 2006.
 Dusan Repovs will give a talk "Topologist sine curve and its many
applications" at Okayama University of Science on January 12, 2007.
[abstract]
Dec. 4, 2006.
 Uploaded pictures taken at the Quinn Conference.
Nov. 11, 2006.
 I learned about a work on 4dimensional surgery obstruction theory
("On stable splitting of homotopy equivalences between smooth 5manifolds ")
by Qayum Khan
So I abondoned the paper
"Knots, links and 4dimensional surgery",
and wrote a new paper
"3manifolds and 4dimensional surgery".
Aug. 22, 2006.
 There will be a birthday conference for Frank Quinn at Binghamton University
from Nov. 5 through Nov. 7.
See the conference page for the detail.
July 30, 2006.
 I extended the result I announced in Hiroshima
to the case of nonsplit links and wrote an article
titled "Knots, links and 4dimensional surgery".
(Revised on Aug. 8.):obsolete!
July 29, 2006.
 I uploaded the pdf file
for my talk "Knots and 4dimensional topological surgery" at
the conference at Hiroshima University. It is written in English.
 July 13, 2006.
 If you like puzzles, try
the slide puzzles of Mitsuo Yoshizawa.
July 1, 2006.
 An article by John Roe entitled
"WHAT IS ... a Coarse Space?"
appeared in the June/July issue of Notices AMS .
His Coarse Mathematics Blog
is very informative.
 June 12, 2006
 Uploaded several pictures I took in Osaka in April
on the Snapshots Page  2006.
June 10, 2006
 I will give a colloquium talk "Knots and 4dimensional surgery"
for nonmathematicians on June 8.
I prepared a pdf file sogori0608.pdf
for the talk.  June 7, 2006.
 Uploaded several pictures
on the Snapshots Page  2006.
May 30, 2006
 An international conference on topology
Intelligence of Low Dimensional Topology
will be held at Hiroshima University, July 22  July 26.
I will probably attend the conference from July 23 to July 25.
 May 12, 2006.
 A RIMS Conference
Methods of Transformation Group Theory
will be at Kyoto University, May 22  May 26.
I will attend the conference from May 22 to May 24.
 May 12, 2006.
 As the 9th volume of G & T Monographs,
"Exotic homology manifolds  Oberwolfach 2003"[Frank Quinn and Andrew Ranicki (editors)]
has been published. Two joint papers (one with Pedersen and the other
with Ranicki) of mine are included.
 April 25, 2006.
 A MiniWorkshop "The Hauptvermutung for HighDimensional Manifolds"
will be held at
Mathematisches Forschungsinstitut Oberwolfach, August 13  19, 2006.
The purpose is to discuss about
Novikov's critique
on the state of the literature on triangulation of manifolds.
 April 4, 2006
[See also Hauptvermutung Page
of Andrew Ranicki.]
 Uploaded the joint senior thesis
"Decomposition of Spaces into Simplices
and Cells" written by my two students, Sachiko Tamura and Rie Namba.
It is written in Japanese, but contains lots of pictures.
 Feb.27, 2006
 Created a photo page
"A Year in Scotland 90/91" .
 Feb. 1, 2006

The first Group Action Forum conference
"Groups in Geometry and Topology" will be held in Malaga, Spain
from 4 to 8 September, 2006. The officila site is
http://agt.cie.uma.es/~ggt06/ .
 Jan. 19, 2006.
 Hegenbarth and Repovs showed that surgery obstruction theory works
in the topological category for certain 4manifolds related to torus knots
in "Applications of controlled surgery in dimension 4: examples".
It seems their argument also works for hyperbolic knots, and I wrote
a short note "Hyperbolic knots and 4dimensional surgery".
>>hyperbolic.pdf
 Jan. 15, 2006.
 I will attend the meeting "Prospects of Topology"
(March 17  19, 2006, Kyushu University).
 Dec. 13, 2005.
 I will attend the meeting "Toward 3 and 4dimensional mathematics"
(Feb. 17  20, 2006, HIroshima University).
 Dec. 13, 2005.
 Prof. Dusan Repovs
(Univ. of Ljubljana, Slovenia) will give a talk
titled "Homology 3 and 4manifolds: A survey" at Okayama University of Science
on January 16, 2006, 4:306:00pm in the seminar room on the 5th floor of Building 20.
[abstract] Nov. 29, 2005
 I will attend the meeting "Topology of Knots VIII" ( Dec. 23  26, 2005, Waseda University).
 Nov. 16, 2005
 There will be two meetings on transformation group theory in November:
Symposium on Transformation Groups (2005)(Nov. 24  26, Osaka)
Workshop on KTheory and Its Applications(Nov. 28  30, Okayama)
 Oct. 22, 2005
 Andrew Ranicki wrote to me about a TV movie titled "Hawking", in which
Roger Penrose convinces Hawking of the value of topology. Visit Andrew's
Surgery Bits and Pieces
page for more information.
Oct. 11, 2005
 Lots of people show a list of their mathematical ancestors on their
web pages. So I made one myself : my ancestors,
consulting The Mathematics Genealogy Project site. According to this site, Hilbert has 11462 descendants.
On the other hand, Poincare has only one descendant [two descendents as of June 19, 2007]!
I wonder what is the difference between them.
Oct. 4, 2005
 Uploaded a picture of an "Alexander's horned sphere" Tshirt
on the Snapshots Page  2005.
Sept. 23, 2005
 A revision of Quinn's math.KT/0402396 paper was posted on September 19th.
It omits material included in math.KT/0509294.
It seems it is not in the final form yet, since section 7 is still missing.
Sept. 21, 2005
 F. Quinn's latest preprint
"Hyperelementary induction for Ktheory of virtually abelian groups" is a sequel to
"Controlled Ktheory I: Basic theory".
He actually told me to work on this stuff for my Ph.D thesis 25 years ago,
but I failed to do so at that time. I do not think I can work it out myself even now.
 Sept. 17, 2005
 I am trying to understand
"Bounded rigidity of manifolds and asymptotic dimension growth" (ChangFerryYu).
This is a really exciting paper to read.
 Sept. 17, 2005
 The Proceedings of the 2003 Oberwolfach MiniWorkshop "Exotic Homology Manifolds"
is now almost in the final form. A pdf file can be obtained at Andrew Ranicki's
Books Page.
 August 7, 2005
 I have been studying the new paper by F. Quinn
"Homology manifolds and 4dimensional surgery" (math.GT/0504258) ,
but I learned today that
"April 2005 version withdrawn May 2005 due to an error in the evendimensional part of the proof"!!!
 May 11, 2005
 I will attend the RIMS conference
"
New Evolution of Transformation Group Theory", 6 June  10 June.
[Controlled surgery with good local fundamental groups (pdf)]
 My affiliation has changed to Department of Applied Science,
Faculty of Science, Okayama University of Science.
 Apr. 1, 2005
 Uploaded a picture of
Quinn's Puzzle
on the Snapshots Page  2005.
Mar. 6, 2005
 I attended
Riemannian Geometry
and Geometric Analysis, from Jan. 10 thru Jan. 13.
I placed two pictures I took in Kyushu
here.
Jan. 15, 2005
 Moved from
http://math.josai.ac.jp/~yamasaki/.
Nov. 28, 2004
 Survey Talk "Surgery Theory and Geometry" presented at
the conference
"Toward the Future of the Topology of Manifolds".
[manuscript(Japanese pdffile)]
[pdffile for presentation(English)]
Nov. 10, 2004
 Uploaded a picture of Billiken figure on the Snapshots page.
Oct. 2004
 Uploaded pictures taken in Sapporo on the Snapshots page.
Sep. 29, 2004
 Created a link page Topology/Geometry Lectures on the Web.  Sep. 2004
 Created a link page Diaries/Essays of mathematicians.  Aug. 13, 2004
 Uploaded pictures taken at the
annual meeting of the Mathematical Society of Japan, Tsukuba, March 2004.
 Apr. 1, 2004
 Created Snapshots page.
 Mar. 8, 2004
 "Stability in Controlled LTheory" (joint with E. K. Pedersen).
[squeeze.pdf]
[revised version]
Feb. 11, 2004
 "Controlled LTheory" (joint with A. Ranicki).
[cltheory.pdf]
[revised version]
Jan. 27, 2004