Our Centre’s Long-Term Engagement with the African Mathematical Community

Over the past years, our research centre has maintained strong and sustained collaborations with mathematicians and academic institutions across Africa. These activities reflect our collective commitment to supporting mathematical research, advanced training, and international cooperation, particularly in regions where access to high-quality supervision remains limited.

Our engagement began several years ago with visits to the African Institute of Mathematical Sciences (AIMS) Ghana, where members of our centre contributed to graduate-level teaching through lecture courses for MSc and PhD students. Further activities included intensive lecture courses in Burkina Faso, supported by the Volkswagen Stiftung (Germany), carried out under challenging circumstances. Despite such difficulties, our group has continued to visit and collaborate with multiple African countries, focusing on capacity building and student support.

Some of these early activities are documented in a research volume edited by members of our group together with international collaborators:

https://link.springer.com/book/10.1007/978-3-030-05657-5

After our centre’s activities expanded to Ghent University, these collaborations continued and strengthened. Notable examples include:

In Ghana, our centre has developed lasting connections with the University of Ghana and the University of Cape Coast. Members of our group have visited both institutions multiple times, delivering advanced lectures and supporting MSc-level training.

Through a Carnegie Corporation of New York (CCNY) grant, Linda Botchway began her PhD at the University of Ghana in 2020. She had previously completed her MSc at AIMS Ghana under supervision linked to our centre, and her PhD work has been supervised within our research network:

After a delay due to maternity leave, her PhD thesis has now been submitted, and the defence is expected to take place soon.

Our collaboration with the University of Addis Ababa has also included PhD supervision and mentoring, sometimes outside formal joint PhD agreements. One such collaboration involved Atile Nega, whose PhD thesis was ready for submission when the COVID-19 pandemic began. Tragically, he passed away shortly before his public defence could be held online.

Many of the students mentioned above were supervised without formal joint-degree frameworks. These activities represent a sustained investment of time and effort by our centre, driven by the recognition that many exceptionally talented students in developing countries face structural barriers to adequate supervision. In several instances, students travelled for days to attend advanced mathematics lectures delivered by members of our group.

In addition to research supervision and teaching, Prof Michael Ruzhansky, for several years, served on the jury of the IBNI Prize for Africa, together with colleagues from France, contributing to the recognition of outstanding mathematical research on the African continent:
https://www.idpoisson.fr/prix-ibni/

Overall, these activities demonstrate our centre’s long-standing commitment to fostering mathematical excellence, international collaboration, and equitable access to advanced mathematical training in Africa.


Congratulations to Dr. Vishvesh Kumar — Assistant Professor at IIT BHU Varanasi

We are delighted to congratulate Dr. Vishvesh Kumar on his new position at Department of Mathematical Sciences at IIT BHU Varanasi as an Assistant Professor. This is a wonderful milestone in his academic career, and a moment of pride for all of us at the Ghent Analysis & PDE Center.

Since joining our group as a postdoctoral researcher at Ghent University, Dr. Kumar has been an active and inspiring member of our community. Working within the Department of Mathematics: Analysis, Logic and Discrete Mathematics and the Ghent Analysis & PDE Center headed by Prof. Michael Ruzhansky, he has contributed significantly to our core areas of research.  

Research contributions in our group

Dr. Kumar’s research lies at the intersection of abstract harmonic analysis, pseudo-differential operators, geometric analysis, and partial differential equations on Lie groups.  

During his time in Ghent, he has:

  • Co-authored numerous papers on nonlocal and subelliptic problems on stratified Lie groups, including work on Brezis–Nirenberg type problems, critical equations, and fractional Sobolev-type inequalities.  
  • Made substantial contributions to the theory of damped and fractional wave equations on graded and stratified Lie groups, including results for higher order hypoelliptic equations with data in negative order Sobolev spaces.  
  • Advanced functional inequalities and harmonic analysis on symmetric spaces and hypergroups, with applications to Fourier multipliers, Strichartz estimates, and related analytic inequalities.  

His work has appeared, or is forthcoming, in several respected international journals such as Journal of Evolution EquationsMathematische AnnalenJournal of Geometric AnalysisIsrael Journal of Mathematics, and others, reflecting both the depth and breadth of his contribution to our field.  

A valued colleague

On a personal level, Vishvesh has been a generous collaborator and a supportive colleague. His willingness to discuss ideas, share expertise, and encourage younger researchers and visitors has left a strong and positive impression in our group. Many of us have benefited from his clarity of thought, his calm problem-solving approach, and his enthusiasm for mathematics.


Looking ahead

While we will miss having him at the Ghent Analysis & PDE Center, we are equally excited to see him take this next step as an Assistant Professor at IIT BHU Varanasi. We are confident that he will continue to build a vibrant research program, inspire students, and develop new collaborations that will further strengthen the links between our institutions.

Warm words from Dr Kumar about group

Congratulations to Dr Junqing Huang!

We are delighted to celebrate the successful PhD defense of Junqing Huang, who presented his dissertation on the topic::

Variational Modeling and (Semi)-sparsity Generalizations for Image Analysis and Processing: Theory, Optimization and Applications

Academic Achievement

Throughout these years, Junqing has shown exceptional commitment to his research, combining deep scientific curiosity with remarkable perseverance.

On a Personal Note

Beyond his academic excellence, Junqing has always brought warmth and positivity to our group. He is genuinely one of the kindest people you will meet — always smiling, always supportive.

Thanks to him, we now have beautiful group logos in multiple versions, and every new member’s photo appears in our cap thanks to his creativity and careful work.

Congratulations once again, Junqing! We are grateful for everything you contributed to our group and wish you the very best in the next chapter of your career. 

Celebrating 15 Years of Collaboration Between Michael Ruzhansky and Kazakhstan’s Mathematicians

At the 15th ISAAC Congress in Astana, Prof. Michael Ruzhansky delivered a public lecture titled: 

Analysis on Groups and Related Topics 
Collaboration with Kazakhstan.

Prof. Ruzhansky shared the story of a remarkable 15-year journey (2010–2025) of academic collaboration with Kazakhstan. Starting from his first lectures at KazNU in 2010, this partnership has grown to include joint research, PhD supervision, and postdoctoral mentorship for many young Kazakhstani scholars.

The collaborations have produced significant results in:

  • Spectral Geometry and subelliptic BVPs: + Suragan, Kalmenov, Sadybekov, Sabitbek, ….
  • Hardy, Rellich, Sobolev, CKN inequalities (weighted, anisotropic, fractional, critical cases): + Suragan, Kassymov, Yessirkegenov, Sabitbek, ….
  • Fourier multipliers and analysis on groups: + Nursultanov, Akylzhanov, Tulenov, Shaimardan
  • Nonharmonic analysis: + Tokmagambetov, Torebek, …
  • Very weak solutions: + Tokmagambetov, Alybay, Yessirkegenov, Shaimardan, Yeskermessuly, …
  • Heat equations: Torebek, Borikhanov, Turmetov, Kompysh, Kassymov, ….
  • Inequalities on Lie groups, measuring spaces: + Suragan, Kassymov, Yessirkegenov, Zaur

Many of these works have been published in leading journals and collected in influential monographs, including Hardy Inequalities on Homogeneous Groups and Spectral Geometry of Partial Differential Operators.

This talk was more than a technical presentation — it was a celebration of friendship, mentorship, and the belief that mathematics knows no borders. The audience left inspired, reminded that sustained collaboration can transform both research landscapes and individual careers.

Here’s to the next 15 years of discovery and cooperation!

Methusalem Colloquium Lecture by Arick Shao

Dr. Arick Shao
Queen Mary University of London

Topic: Scattering and Asymptotics for Critically Weakly Hyperbolic and Singular Systems
Time: 14:30 – 15:30 CET (14 and 15 April, 2025)
Where: Leslokaal 3.1 (Krijgslaan 281, Building S8, Ghent University)

We study a very general class of first-order linear hyperbolic systems that both become weakly hyperbolic and contain singular lower-order coefficients at a single time t = 0. In critically weakly hyperbolic settings, it is well-known that solutions lose a finite amount of regularity at t = 0. Here, we both improve upon the analysis in the weakly hyperbolic setting, and we extend this analysis to systems containing critically singular coefficients, which may also exhibit modified asymptotics and regularity loss at t = 0. In particular, we give precise quantifications for (1) the asymptotics of solutions as t approaches 0, (2) the scattering problem of solving the system with asymptotic data at t = 0, and (3) the loss of regularity due to the degeneracies at t = 0. Finally, we discuss a wide range of applications for these results, including weakly hyperbolic wave equations (and equations of higher order), as well as equations arising
from relativity and cosmology (e.g. at big bang singularities).
This is joint work with Bolys Sabitbek (QMUL). 

Congratulations to Durvudkhan Suragan!

Congratulations to Dr. Durvudkhan Suragan on being awarded the prestigious 

Order of Kurmet

by the President of Kazakhstan! The Order of Kurmet (Order of Honour) is a state award established in 1993, recognizing outstanding contributions in the fields of economics, science, culture, social development, and education.

Congratulations to Aidyn and Nurgissa!

Congratulations to Aidyn Kassymov and Nurgissa Yessirkegenov for receiving the nomination of

The Best Researcher Kazakhstan 2024

Their exceptional research contributions have greatly advanced our understanding of various fields, making them a deserving candidate for the Best Researcher nomination in Kazakhstan for 2024. We are proud to recognize their unwavering commitment to innovation and excellence, which inspires peers and students alike. This nomination not only highlights their remarkable achievements but also underscores their significant impact on the research community in Kazakhstan.

Congratulations to Joel Restrepo!

Huge Congratulations, Joel Restrepo!

We are thrilled to share the amazing news that our group member, Joel Restrepo, has secured a permanent position at the Mathematics Department of the CINVESTAV in Mexico.

Joel’s achievement is truly remarkable and serves as an inspiration to all of us. His hard work and talent have led to this well-deserved milestone, and we couldn’t be prouder. Since joining our Ghent Analysis & PDE Center in 2022, Joel Restrepo has published 5 papers and organised numerous conferences and workshops, showcasing his dedication and leadership in our academic community.

We wholeheartedly congratulate Joel on this incredible accomplishment and wish him continued success in this new chapter of his career. Your contributions to the Ghent Analysis & PDE Center are bound to make a lasting impact, and we are honored to have you as part of our group.