Abstract :
More than twenty-five years ago, astronomers discovered that the expansion of the Universe is accelerating. The cause of this acceleration, commonly called dark energy, remains one of the greatest mysteries in modern physics. The simplest explanation is that dark energy is a constant property of empty space, but recent observations have raised the intriguing possibility that it may evolve over cosmic time.
In this talk, I will briefly introduce the dark energy problem and explain how cosmologists use different observations to test ideas about its nature. I will review the current observational situation, discuss what we can and cannot conclude from the available data, and describe how new experiments, including the Euclid mission, may help us uncover whether dark energy is truly constant or a sign of new physics.
Bio: Martin Kunz is Professor of Cosmology in the Department of Theoretical Physics at the University of Geneva. His research focuses on the nature of dark energy, the large-scale structure of the Universe, and the development of statistical methods for cosmological data analysis. He has contributed extensively to the theoretical modeling and observational study of dark energy and is currently Chair of the Euclid Collaboration Board, overseeing one of the largest international efforts to map the dark Universe.
