SFI External Professor Constantino Tsallis (Centro Brasileiro de Pesquisas Físicas) will serve as co-chair and synthesis lead of the 2027 Nobel Symposium in Physics, “Beyond Boltzmann: Complexity, Memory, and Non-Additive Entropies,” taking place May 24–28, 2027, in Bäckaskog, Sweden. The symposium was announced this spring.
Tsallis proposed the symposium with Roman Pasechnik (Lund University), who serves as symposium chair. The meeting will bring together researchers to assess developments in generalized statistical mechanics and related fields, at a time when new data, theory, and computational tools are making it possible to better test these ideas.
The symposium centers on a framework Tsallis first published in 1988, extending classical Boltzmann-Gibbs statistical mechanics to describe complex systems where the standard theory no longer fully applies. The framework has, over the years, received extensive high-precision experimental validation across a wide range of systems, from motion of granular matter and high-energy collisions to cosmological observations and medical applications, and has enabled analytically exact calculations across diverse areas of physics, providing both experimental grounding and theoretical predictability.
As Tsallis notes, the key difference between traditional approaches and this framework lies in how they account for complexity. The symposium will focus on consolidating decades of work on this framework, as the field converges on shared concepts and standards, and works to clarify key open questions. “It’s a fantastic occasion to make a synthesis of what has been done and help identify directions for the future,” Tsallis says.
As synthesis lead, Tsallis will deliver a closing lecture, bringing together insights from across the meeting and outlining key directions for future research.