Virtual lecture: Babelsberg Starry Night on 18 December 2025

WMAP_Expansion_Universe

Since the Big Bang about 14 billion years ago, the Universe has been expanding. The expansion rate is given by the Hubble constant, its exact value is still under debate.

Credit: NASA/WMAP Science Team
Dec. 17, 2025 //

The next lecture of the Virtual Babelsberg Starry Nights of the Leibniz Institute for Astrophysics Potsdam (AIP) entitled “What’s wrong with the Hubble constant” (in German) by Prof. Dr. Matthias Steinmetz, will focus on this constant and the expansion of the Universe. The video of the lecture will be broadcast on the YouTube channel “Urknall, Weltall und das Leben” (Big Bang, Universe and Life) from Thursday, 18.12.2025.

Prof. Dr. Matthias Steinmetz is a scientific director at the AIP and talks in this public lecture about the Hubble constant. This quantity describes the current expansion rate of the Universe and is central to our understanding of its age and evolution. However, despite more precise measurement methods—from standard candles such as supernovae to acoustic oscillations in the early cosmos—the results show discrepancies. Is the cause systematic errors in the measurements, or does this point to new physics beyond the Standard Model? In this lecture, Matthias Steinmetz sheds light on the background to this fundamental discrepancy and discusses the most promising approaches.

Usually on the 3rd Thursday of each month, starting at 8 p.m., the lectures of the Babelsberg Starry Nights become available at

https://www.aip.de/babelsberger-sternennaechte

and via the YouTube channels "Urknall, Weltall und das Leben" (Big Bang, Universe and Life) and "videowissen" and can be viewed afterwards at any time.

WMAP_Expansion_Universe

Since the Big Bang about 14 billion years ago, the Universe has been expanding. The expansion rate is given by the Hubble constant, its exact value is still under debate.

Credit: NASA/WMAP Science Team
Dec. 17, 2025 //

The next lecture of the Virtual Babelsberg Starry Nights of the Leibniz Institute for Astrophysics Potsdam (AIP) entitled “What’s wrong with the Hubble constant” (in German) by Prof. Dr. Matthias Steinmetz, will focus on this constant and the expansion of the Universe. The video of the lecture will be broadcast on the YouTube channel “Urknall, Weltall und das Leben” (Big Bang, Universe and Life) from Thursday, 18.12.2025.

Prof. Dr. Matthias Steinmetz is a scientific director at the AIP and talks in this public lecture about the Hubble constant. This quantity describes the current expansion rate of the Universe and is central to our understanding of its age and evolution. However, despite more precise measurement methods—from standard candles such as supernovae to acoustic oscillations in the early cosmos—the results show discrepancies. Is the cause systematic errors in the measurements, or does this point to new physics beyond the Standard Model? In this lecture, Matthias Steinmetz sheds light on the background to this fundamental discrepancy and discusses the most promising approaches.

Usually on the 3rd Thursday of each month, starting at 8 p.m., the lectures of the Babelsberg Starry Nights become available at

https://www.aip.de/babelsberger-sternennaechte

and via the YouTube channels "Urknall, Weltall und das Leben" (Big Bang, Universe and Life) and "videowissen" and can be viewed afterwards at any time.

The Leibniz Institute for Astrophysics Potsdam (AIP) is dedicated to astrophysical questions ranging from the study of our sun to the evolution of the cosmos. The key areas of research focus on stellar, solar and exoplanetary physics as well as extragalactic astrophysics. A considerable part of the institute's efforts aims at the development of research technology in the fields of spectroscopy, robotic telescopes, and e-science. The AIP is the successor of the Berlin Observatory founded in 1700 and of the Astrophysical Observatory of Potsdam founded in 1874. The latter was the world’s first observatory to emphasize explicitly the research area of astrophysics. The AIP has been a member of the Leibniz Association since 1992.
Last update: 17. December 2025