Self-genericity axioms IV

Speaker: 

Andres Forero

Institution: 

UCI

Time: 

Monday, April 14, 2014 - 4:00pm to 5:30pm

Host: 

Location: 

RH 440R

We continue the exposition on self-genericity axioms for ideals on P(Z) (Club Catch, Projective Catch and Stationary Catch). We have established some relations with forcing axioms and with the existence of certain regular forcing embeddings and projections, and also point out connections with Precipitousness. We give an rough overview of the method used for proving the existence of models with Woodin cardinals coming from these axioms, using the Core Model Theory. In this talk we explain one of the main technique used in the argument, namely the frequent extension argument.

Efficient operator factorizations for integral and differential equations

Speaker: 

Kenneth Ho

Institution: 

Stanford

Time: 

Monday, May 12, 2014 - 4:00pm to 5:00pm

Host: 

Location: 

RH306

Fast algorithms for elliptic PDEs are central to modern scientific computing. In this talk, we consider the efficient factorization of matrices associated with elliptic problems in both integral and differential form. A key starting point is the nested dissection multifrontal method for PDEs, which can be viewed as an LU factorization with a cost which grows with the spatial dimension. Our primary contributions are twofold: (1) a reformulation of previous fast direct solvers for integral equations as multifrontal-like generalized LU decompositions; and (2) a recursive dimensional reduction strategy to achieve optimal linear or nearly linear complexity in 2D and 3D. Our method is fully adaptive and can handle both boundary and volume problems, and furthermore reveals the close connection between structured dense matrices and sparse ones. This is joint work with Lexing Ying.

Self-genericity axioms III

Speaker: 

Andres Forero

Institution: 

UCI

Time: 

Monday, April 7, 2014 - 4:00pm to 5:30pm

Host: 

Location: 

RH 440R

We continue the exposition on self-genericity axioms for ideals on P(Z) (Club Catch, Projective Catch and Stationary Catch). We establish some relations with forcing axioms and with the existence of certain regular forcing embeddings, and also point out connections with Precipitousness. In particular we observe that if Projective Catch holds for an ideal, then that ideal is precipitous, and the converse holds for ideals that concentrate on countable sets. Finally we give an overview of the method used for proving the existence of models with Woodin cardinals coming from these axioms, using the Core Model Theory.

From the mathematics of voting to the mathematics of astronomy

Speaker: 

Donald Saari

Institution: 

UC Irvine

Time: 

Friday, May 9, 2014 - 4:00pm

Location: 

MSTB 120

Two very different mathematical topics, where one comes from the social sciences and the other from the physical sciences.  It is easy to expect that they have nothing to do with one another.  Instead, and as it will be developed in this talk,  thanks to connecting power of  mathematics, they share several relationships.

Self-genericity axioms II

Speaker: 

Andres Forero

Institution: 

UCI

Time: 

Monday, March 31, 2014 - 4:00pm to 5:30pm

Host: 

Location: 

RH 440R

We continue the exposition on self-genericity axioms for ideals on P(Z) (Club Catch, Projective Catch and Stationary Catch). We establish some relations with forcing axioms and with the existence of certain regular forcing embeddings, and also point out connections with Precipitousness. In particular we observe that if Projective Catch holds for an ideal, then that ideal is precipitous, and the converse holds for ideals that concentrate on countable sets. Finally we give an overview of the method used for proving the existence of models with Woodin cardinals coming from these axioms, using the Core Model Theory.

Pages

Subscribe to UCI Mathematics RSS