It is with great sadness that we announce the passing of Prof. Dr. Alexei A. Starobinsky, Associate Editor of Universe, on 21 December 2023.

Prof. Dr. Starobinsky obtained his Ph.D. in theoretical and mathematical physics from the Landau Institute for Theoretical Physics of the Russian Academy of Sciences in 1975. Following the completion of his doctorate, he continued working at the Landau Institute as a research scientist. From 1990 to 1997, he headed the institute's department of gravitation and cosmology. In 1997, he was elected as a member of the Russian Academy of Sciences and became the institute's principal research scientist. From 1999 to 2003, he held the position of the institute's deputy director. Together with Alan Guth and Andrei Linde, he received the 2014 Kavli Prize in Astrophysics “for pioneering the theory of cosmic inflation”. In 2019, he received, together with Viatcheslav Mukhanov and Rashid Sunyaev, the Dirac Medal (ICTP).

Prof. Dr. Starobinsky was renowned for his significant contributions to the field of theoretical and mathematical physics, particularly in the area of cosmology. His groundbreaking work on cosmic inflation theory and super-radiance and the creation of particles by rotating black holes has had a profound impact on our understanding of the early universe.

Prof. Dr. Starobinsky joined our Editorial Board as an Advisory Board Member in July 2018 and became an Associate Editor in August 2020, bringing with him a wealth of knowledge and expertise in his field. In 2020, he co-edited a Special Issue titled “Selected Papers from the 17th Russian Gravitational Conference-International Conference on Gravitation, Cosmology and Astrophysics (RUSGRAV-17)” alongside Vladimir M. Mostepanenko and Elena N. Velichko, which received significant attention from the scientific community. As a referee, his reports were never merely perfunctory; on the contrary, they were always thorough and rich in valuable critical remarks which helped the authors even when rejection was recommended. The Editor-in-Chief often sought his precious advice, which Prof. Dr. Starobinsky never refused, being of great help in so many final decisions.

His passing is a significant loss to the academic community as well as to those who knew him personally. We deeply feel his absence at Universe and offer our sincerest condolences to his family, friends, and colleagues.