L-functional analysis

We are pleased to report that the recent RGOSA seminar featuring the esteemed Marten Wortel was a resounding success! Marten Wortel, along with his collaborators, provided a captivating exploration into the realm of L-functional analysis, drawing upon foundational work and recent developments in the field.

A Brief Recap of the Talk

The seminar centered on “L-functional analysis“, where traditional scalars in functional analysis (R or C) are replaced by a (real or complex) Dedekind complete unital f-algebra L. Marten Wortel’s presentation commenced with a detailed introduction to the theoretical underpinnings of the study, highlighting its significance and the novel perspectives it introduces into the analysis using ordered structures.

Marten provided insights into the collaborative research conducted with Walt van Amstel, Eder Kikianty, Miek Messerschmidt, Luan Naude, Chris Schwanke, Jan Harm van der Walt from Pretoria, and Mark Roelands from Leiden. The discussion illuminated their pioneering work on L-Banach and L-Hilbert spaces and presented comparative analyses with the classical approaches, enriching the attendees’ understanding of the subject.

Access the Seminar Materials

For those who were unable to attend the seminar or wish to revisit the insightful discussions, we have made both the video recording and the presentation slides available below.

Machine Learning Frameworks

Dr. Mohamed Kadhem Karray has just delivered his lecture at the RGOSA seminar series, titled “Machine Learning Frameworks“.

The abstract of his talk is as follows:

“We aim to present the essential mathematical concepts and results of machine and deep learning. In this first lecture, we define precisely the Machine Learning (ML) frameworks and give the first results on “performance guarantee” of ML algorithms in the case of a finite class of hypothesis. The following lessons extend these results to the case of infinite classes (even of infinite dimension).”

Dr. Mohamed Kadhem Karray also has a Youtube channel in which he explains the mathematical aspects of Machine Learning.

Please find the seminar video attached, and the presentation slides below.

Machine Learning Frameworks

We are delighted to welcome researcher Mohamed Kadhem Karray at the RGOSA seminar, where he will be presenting a talk titled “Machine Learning Frameworks” on Thursday, October 19th, at 2:00 PM Tunisian time. Despite his position as a researcher in the industry, Dr. Mohamed Kadhem Karray holds expertise in mathematics. Consequently, his presentation will delve into mathematical aspects, and the abstract of his talk is as follows:

“We aim to present the essential mathematical concepts and results of machine and deep learning. In this first lecture, we define precisely the Machine Learning (ML) frameworks and give the first results on “performance guarantee” of ML algorithms in the case of a finite class of hypothesis. The following lessons extend these results to the case of infinite classes (even of infinite dimension).”

Dr. Mohamed Kadhem Karray also has a Youtube channel in which he explains the mathematical aspects of Machine Learning.

The recordings and presentation slides from the previous talks are available on the seminar’s webpage: https://rgosa.net/seminar/season-2023-2024/

And the link for the zoom conference is:

https://holbertonschool.zoom.us/j/87301682503?pwd=OUY0enlidXYvWHJCeGlTOVF0OVJqUT09

Category measures, the dual of the Dedekind completion of C(K) spaces and hyper-Stonean spaces

Professor Jan Harm van der Walt from the University of Pretoria has just delivered his lecture at the RGOSA seminar series, titled “Category measures, the dual of {C(K)^\delta} and hyper-Stonean spaces”.

The abstract of the talk is here:

For a compact Hausdorff space {K}, we give descriptions of the dual of {C(K)^\delta}, the Dedekind completion of the Banach lattice {C(K)} of continuous, real-valued functions on {K}. We characterize those functionals which are {\sigma}-order continuous and order continuous, respectively, in terms of Oxtoby’s category measures. As applications, we give a purely topological characterization of hyper-Stonean spaces, and characterize those spaces {K} for which {C(K)} admits a strictly positive order continuous functional.

Please find the seminar video attached, and the presentation slides below.

Nonlinear Perron-Frobenius Theory: Part 2

Professor Bas Lemmens has just delivered the final part of his lecture at the RGOSA seminar series, titled “Nonlinear Perron-Frobenius Theory: Part 2.” We look forward to reconvening next week for Part 2.

Please find the seminar video attached, and the presentation slides below.

And the slides are here:

Nonlinear Perron-Frobenius Theory: Part 1

Professor Bas Lemmens has just delivered his inaugural lecture at the RGOSA seminar series, titled “Nonlinear Perron-Frobenius Theory: Part 1.” We look forward to reconvening next week for Part 2.

Please find the seminar video attached, and the presentation slides below.

Nonlinear Perron-Frobenius Theory

For Bas Lemmens a mathematician is

Somebody who explores some relevant abstract structures.

We are delighted to officially announce the commencement of the new RGOSA seminar season. We are thrilled to start this year’s series with a distinguished guest, Pr. Bas Lemmens.

The seminars are scheduled to take place every Thursday at 2:00 PM Tunis time (Tunisia). Your participation and engagement are highly encouraged as we embark on this enlightening journey of knowledge sharing.

The link for the seminar is below:

https://holbertonschool.zoom.us/j/87301682503?pwd=OUY0enlidXYvWHJCeGlTOVF0OVJqUT09

This Thursday, September 7, 2023 and the following Thursday, Pr. Bas Lemmens will talk about:

Nonlinear Perron-Frobenius Theory

The abstract of his talks is: 

Sometimes in mathematics a simple-looking observation opens up a new road to a fertile field. Such an observation was made independently by Garrett Birkhoff and Hans Samelson, who remarked that one can use Hilbert’s (projective) metric and the contraction mapping principle to prove some of the theorems of Perron and Frobenius concerning eigenvectors and eigenvalues of nonnegative matrices. This idea has been pivotal for the development of nonlinear Perron–Frobenius theory.
In the past few decades a number of strikingly detailed nonlinear extensions of Perron–Frobenius theory have been obtained. These results provide an extensive analysis of the eigenvectors and eigenvalues of various classes of order-preserving (monotone) nonlinear maps and give information about their iterative behavior and periodic orbits. They have found applications in computer science, mathematical biology, game theory and the study of dynamical systems.  

This two-part lecture provides an introduction to nonlinear Perron-Frobenius theory.