|
|
CALENDAR OF EVENTS
FOR THE WEEKS OF
MAY 5-9, 2008 (Final Examinations Week)
Revised - MAY 12-16, 2008 (Final Examination Week)
This is the final calendar for the Spring 2008 semester.
Announcements for any seminars after this week will be distributed individually.
The calendar will resume September 2008. |
last update: 5/09/08; 10:50 AM |
| MAY 5-9, 2008 (Final Examinations Week) |
| MONDAY, 5/05/08 |
|
DYNAMICAL SYSTEMS SEMINAR
(R. Sacker)
No seminar this week
|
MONDAY, 5/05/08
3:00-3:30 PM
KAP 248 |
|
MATHEMATICS TEA
You are cordially invited to attend
|
| MONDAY, 5/05/08 |
|
CENTER FOR APPLIED MATHEMATICS SEMINAR
(A. Tartakovsky/C. Wang)
No seminar this week
|
| MONDAY, 5/05/08 |
|
ALGEBRA SEMINAR
(T. Geisser/R. Guralnick/S. Montgomery)
No seminar this week
|
MONDAY, 5/05/08
4:30-5:30 PM
KAP 249 |
|
GEOMETRY & TOPOLOGY SEMINAR
(F. Bonahon)
Nathan Habegger, University of Nantes, France
On the work of Xiao-Song Lin; from classical to quantum topology
Abstract:
In 1954, John Milnor introduced the notion of link homotopy and his invariants of links which he used to classify 3 component links up to homotopy. In 1987 the speaker and XS Lin acheived the classification, for any number of components, essentially by refining the Milnor invariants.
The Habegger-Lin classification scheme was extended to other equivalence relations in Lin's thesis and to more general concordance-type relations satisfying a list of 6 axioms. Axioms 1-4 are local, axiom 5 says that any string link (or 'pure tangle' as in pure braid) has an inverse, while axiom 6 says the equivalence relation on links is generated by isotopy and the equivalence relation on string links (every string link yields a link after 'closure').
In the early 90's Birman and Lin studied the work of Vassiliev on links and described in simple terms the Vassiliev filtration. Bar-Natan adopted their description as a definition of 'finite type' invariants and eventually all this was tied back to the perturbative Chern Simons quantum invariants via the Kontsevich Integral.
Early on, Lin suggested the Milnor invariants were of finite type, but this is strictly true only of the string link invariants because Milnor's invariants are only 'partially' defined, i.e. their indeterminacy depends on the lower order invariants. The speaker and G. Masbaum actually gave in 1997 a formula computing the Milnor string link invariants from the Kontsevich Integral. The tree-like Feynman diagrams correspond to the Milnor invariants.
The nagging problem that Vassiliev invariants of links are universally defined, but Milnor invariants, which ultimately gave the link-homotopy classification, are only partially defined, suggests that finite-type invariants of links are deficient. It turns out that axiom 6 of the aforementioned classification sheme is not satisfied so that Vassiliev (finite type) invariants of links can and ought to be refined, as shown in a recent preprint by the speaker and JB Meilhan.
|
| |
|
|
| TUESDAY, 5/06/08 |
|
GRADUATE STUDENT ANALYSIS SEMINAR
(I. Kukavica/M. Ziane)
No seminar this week
|
TUESDAY, 5/06/08
12:00-12:30 PM
KAP 248 |
|
USC WOMEN IN MATH TEA
You are cordially invited to attend
|
TUESDAY, 5/06/08
12:30-2:30 PM
KAP 249 |
|
USC WOMEN IN MATH
(C. Haskell)
| Film Screening: Julia Robinson and Hilbert's 10th Problem |
About the movie:
`Julia Robinson and Hilbert's 10th Problem' is a documentary about Julia Robinson. Julia Robinson was the first woman elected to the mathematical section of the National Academy of Sciences, and the first woman to become president of the American Mathematical Society. While tracing her contribution to the solution of Hilbert's 10th problem, the film illuminates how her work led to an unusual friendship between Russian and American colleagues at the height of the Cold War.
The film is directed by George Csicsery and was made possible with grants from Margaret and Will Hearst and the Clay Mathematics Institute. The film is about one hour long with an additional 30 minutes of extra features.
|
TUESDAY, 5/06/08
2:30-3:00 PM
KAP 248 |
|
SPECIAL MATHEMATICS TEA
You are cordially invited to attend |
TUESDAY, 5/06/08
3:00-4:00 PM
KAP 249 |
|
GRADUATE STUDENT COLLOQUIUM
(G. Rosen)
Joseph F. Grcar, Lawrence Berkeley National Laboratory
John von Neumann and the Origins of Scientific Computing
Abstract:
The invention of modern computers (those digital, electronic, and programmable) in the mid 1940s represented a paradigm shift in what could be achieved through calculation. Manual scientific computing had been practiced from around the time of Carl Friedrich Gauss, in the form of astronomical calculations for marine navigation and geodetic calculations for cartography. By the end of World War II, John von Neumann was perfectly situated to understand both the advances that could be realized from mechanization and the whole range of technical obstacles that had to be overcome. Thus von Neumann and his principal collaborator in this work, Herman Goldstine, sought to reinvent scientific computing. As a necessary prerequisite they envisaged a rejuvenated “approximation mathematics” which is now numerical analysis, and they created what is now computer science though a series of influential reports that described the design and use of the computers then being built first at the University of Pennsylvania and then at the Institute for Advanced Study. This talk surveys the development of scientific computing from Gauss to the first electronic calculations in the early 1950s. The emphasis is not von Neumann himself but rather the conceptual changes that occurred, many of which can be traced to him. If time permits it may also be possible to sketch his biography.
|
| |
|
|
| WEDNESDAY, 5/07/08 |
|
PI MU EPSILON (Undergraduate Honors Society)
(R. Arratia/S. Lototsky)
No more meetings for the semester.
|
WEDNESDAY, 5/07/08
3:00-3:30 PM
KAP 248 |
|
MATHEMATICS TEA
You are cordially invited to attend
|
WEDNESDAY, 5/07/08
3:30-4:30 PM
KAP 249 |
|
MATHEMATICAL COLLOQUIUM
(J. Fulman/J. He)
Simeon Reich, Technion – Israel Institute of Technology
Continuous semigroups of holomorphic mappings
Abstract:
After presenting a brief survey of recent progress in the theory of continuous semigroups of holomorphic mappings in the context of nonlinear semigroup theory, we intend to concentrate on two new rigidity theorems for holomorphic generators. More precisely, let f be the holomorphic generator of a one-parameter continuous semigroup of self-mappings \left\{F_t\right\}_{t\geq 0} of the open unit ball \mathbb{B} in a complex Hilbert space H. We show that if the weak restricted limit of \frac{f(x)}{\| x-\tau\|^3} equals~0 at some boundary point \tau\in\partial\mathbb{B}, then
f(x)\equiv 0 on \mathbb{B}. For the one-dimensional case, where f is a holomorphic generator on the open unit disk \Delta of the complex plane \mathbb{C}, we prove it is enough to assume that \lim\limits_{k\rightarrow\infty}\frac{f(z_k)}{(z_k-\tau)^3}=0 for some sequence \{z_k\}_{k=1}^{\infty}\subset\Delta converging nontangentially to \tau\in\partial\Delta. This lecture is based on joint work with M. Elin, M. Levenshtein and D. Shoikhet.
|
| |
|
|
| THURSDAY, 5/08/08 |
|
No seminars today. |
| |
|
|
| FRIDAY, 5/09/08 |
|
GRADUATE STUDENT GEOMETRY & TOPOLOGY SEMINAR
(R. Golovko)
No seminar this week
|
| FRIDAY, 5/09/08 |
|
ANALYSIS SEMINAR
(S. Friedlander/I. Kukavica)
No seminar this week
|
FRIDAY, 5/09/08
2:45-3:30 PM
KAP 248 |
|
GRADUATE MATHEMATICS TEA
You are cordially invited to attend
|
| FRIDAY, 5/09/08 |
|
PROBABILITY & STATISTICS SEMINAR
(J. Bartroff/N. Zygouras)No seminar this week
|
| |
|
|
Revised - MAY 12-16, 2008 (Final Examinations Week)
This is the final calendar for the Spring 2008 semester.
*** Denotes the change |
| MONDAY, 5/12/08 |
|
DYNAMICAL SYSTEMS SEMINAR
(R. Sacker)
No seminar today
|
| MONDAY, 5/12/08 |
|
CENTER FOR APPLIED MATHEMATICS SEMINAR
(A. Tartakovsky/C. Wang)
No seminar today
|
| MONDAY, 5/12/08 |
|
ALGEBRA SEMINAR
(T. Geisser/R. Guralnick/S. Montgomery)
No seminar today
|
| MONDAY, 5/12/08 |
|
GEOMETRY & TOPOLOGY SEMINAR
(F. Bonahon)
No seminar today
|
| |
|
|
TUESDAY, 5/13/08
11:00 AM-1:00 PM
DRB 337 |
|
GRADUATE STUDENT ANALYSIS SEMINAR
(I. Kukavica/M. Ziane)
Ednei Reis, University of Southern California
Littlewood-Paleytheory III
Vlad Vicol, University of Southern California
Estimates of the Oseen kernel
|
| |
|
|
| WEDNESDAY, 5/14/08 |
|
PI MU EPSILON (Undergraduate Honors Society)
(R. Arratia/S. Lototsky)
No more meeting for the semester
|
| WEDNESDAY, 5/14/08 |
|
MATHEMATICAL COLLOQUIUM
(J. Fulman/J. He)
No seminar today
|
| |
|
|
| THURSDAY, 5/15/08 |
|
No seminars today
|
| |
|
|
FRIDAY, 5/16/08
12:00-2:00 PM
KAP 116 (Math Center) |
|
GRADUATION RECEPTION
You are cordially invited to attend
|
| FRIDAY, 5/16/08 |
|
GRADUATE STUDENT GEOMETRY & TOPOLOGY SEMINAR
(R. Golovko)
No seminar today
|
| FRIDAY, 5/16/08 |
|
ANALYSIS SEMINAR
(S. Friedlander/I. Kukavica)
No seminar today
|
| FRIDAY, 5/16/08 |
|
PROBABILITY & STATISTICS SEMINAR
(J. Bartroff/N. Zygouras)
No seminar today
|
| |
|
|
|
