This blogpost was authored by Dr. Chittaranjan Hens, who is an Assistant Professor at the International Institute of Information Technology, Hyderabad (IIITH), India, working in the Center for Computational Natural Sciences and Bioinformatics (CCNSB). Dr. Hens visited the University of Bristol in Autumn 2024 to collaborate with Professor Luca Giuggioli in the School of Engineering Mathematics and Technology on the project ‘Disease propagation in complex networks: a biased random walk approach’.
The research topic
The collaboration aims to investigate the dynamics of information diffusion across networks, while acknowledging that these dynamics are strongly influenced by the network’s structure and the specific dynamical mechanisms at work.
Luca makes significant contributions to random walk problems in two-dimensional space, where the space may contain various types of obstacles. A systematic analysis captures the occupation probability at any time and location within the specified domain. This occupation probability can also be used to calculate the mean first passage time, which is an important component of understanding random walk problems because it relates real-world search problems in biology from animals to cells and in engineering from mechanical oscillators to computer networks. This compelling analysis allows us to investigate random walks in both regular and non-regular lattices. The obstacle that Luca mentioned appeared in the network as link rewiring or shortcut. We have established a strong connection between the structural complexity emerging from non-regular networks and cutting-edge analytical tools capable of capturing the movement of random walks in heterogeneous media (in our case, heterogeneous graphs).
Outcomes of the visit to Bristol
The collaboration has been both intellectually stimulating and deeply rewarding. We anticipate finalizing an engaging and insightful research draft soon. Additionally, my former PhD student, Subrata, has been actively contributing to the development of our paper.
Beyond the research, my experience at Bristol was equally enriching. I delivered three talks at the department, two of which were designed for a broad audience. The discussions that followed were lively, with insightful questions that pushed the conversation further. Luca’s PhD student, Dan, who had limited prior exposure to network science, quickly grasped the essence of my work. He and Luca offered valuable perspectives on how their analytical methods could enhance my research—this made the whole exchange not only productive but also thoroughly enjoyable. And the best part? It remains enjoyable even now as we continue our discussions!
Stepping outside the realm of equations and networks, I found the cultural and social discussions with Luca and Dan equally fascinating. Despite our varied backgrounds, we uncovered numerous shared viewpoints on global issues, reaffirming that intellectual and social bridges can transcend cultural boundaries.
Exploring Bristol
Bristol itself holds a special place in my journey. Years ago, I stood before Banksy’s “The Flower Thrower” in Bethlehem—one of his most iconic works. So, arriving in Bristol, his hometown, felt like a full-circle moment. I took the time to track down some of his works, including “Well Hung Lover,” and found the experience thrilling.
Before my visit to Bristol, I spent time in Oxford, where I reflected on the legacy of Ada Lovelace, a visionary who played a pivotal role in shaping Charles Babbage’s Analytical Engine, a precursor to modern computing. To my delight, I later discovered that my office building in Bristol was named after her. Another powerful moment came when I encountered the life-size bronze statue of Henrietta Lacks near the Physics Department. Lacks, an African American woman, unknowingly contributed to one of the most significant medical breakthroughs when her cells were taken without consent—her story stands as a reminder of the need for inclusivity, respect, and ethical responsibility in science.
A final delightful surprise awaited me near College Green, where I stumbled upon a statue of Raja Ram Mohan Roy—the “father of the Indian Renaissance.” Born in my own district in India, he was a fearless reformer who campaigned against oppressive practices such as “Sati” (a custom that existed in a subset of upper caste society in Bengal, in which the widow was burned alive alongside her deceased husband). Seeing his presence in Bristol was both unexpected and deeply moving.
This collaboration has been more than just an academic exercise; it has been a journey of discovery—scientific, cultural, and personal. It has reinforced the importance of interdisciplinary thinking, historical awareness, and the role we play in shaping a more inclusive and enlightened world. In a time of global turmoil, such exchanges—whether in science or in culture—serve as powerful reminders of our collective responsibility to push boundaries, foster diversity, and create meaningful progress.
