4 papers
A Constructive Cayley Representation of Orthogonal Matrices and Applications to Optimization
Iwo Biborski
It is known that every real orthogonal matrix can be brought into the domain of the Cayley transform by multiplication with a suitable diagonal signature matrix. In this paper we p…
Note on the spread of real symmetric matrices with entries in fixed interval
Iwo Biborski
The spread of a matrix is defined as the maximum of distances between any two eigenvalues of that matrix. In this paper we investigate spread maximization as a function on compact…
Solutions of quasianalytic equations
Andre Belotto da Silva, Iwo Biborski, Edward Bierstone
The article develops techniques for solving equations G(x,y)=0, where G(x,y)=G(x_1,...,x_n,y) is a function in a given quasianalytic class (for example, a quasianalytic Denjoy-Carl…
On the geometric and differential properties of closed sets definable in quasianalytic structures
Iwo Biborski
In this paper we show that the equivalences between certain properties of closed subanalytic sets proved by E. Bierstone and P. Milman in \cite{[BM-1]} hold for closed sets definab…