Research projects

Period: 01.10.2024—30.09.2027

PI: Prof. Elmo Tempel

Partner institutes:

• The Leibniz Institute for Astrophysics Potsdam (AIP), Germany
  Lead person:  Dr. Noam Libeskind
• Kapteyn Institute, University of Groningen, the Netherlands
  Lead person: Prof. Rien van de Weygaert
• Institut Élie Cartan de Lorraine, Nancy, France
  Lead person: Prof. Radu S. Stoica

Funder: Horizon Europe (Horizon Twinning)
Total Funding: 1 499 600 eur

The current era of large astronomical surveys and simulations produces massive amounts of new data. When combined with new analytical frameworks, it will allow for statistical inference to tackle many unsolved questions, such as the role of the cosmic web in the formation and evolution of galaxies. The current observations show the environment of galaxies plays a major role in the star formation quenching, mass assembly, and even the orientation of the galaxies in the cosmic web filaments. To succeed in studies like this requires combining knowledge and experience in observations, cosmological simulations, cosmic web theory, and applied mathematics. This proposal aims to strengthen the research capacity of the University of Tartu (UTARTU) in these subjects. The advanced partners of the project are internationally renowned experts in hydrodynamical simulations, cosmic web theory, cosmic web finders, and applied geometric and spatial analysis. Thanks to the knowledge transfer from advanced partners, this project will provide UTARTU with the required expertise to actively participate in the next-generation galaxy evolution surveys that allow mapping of the cosmic web in unprecedented detail. In collaboration with the partners, an improved method for cosmic web modelling will be developed that builds on the experience of the Bisous model (developed in UTARTU) and other cosmic web finders that the partners have developed. This new GalaxyWeb model aims to simultaneously detect the groups and filaments directly from the observed redshifts of galaxies and work efficiently with significantly higher target densities and the non-trivial selection functions of the next-generation surveys. This twinning proposal will help ensure long-term mutually beneficial collaboration between the four project partners, raise the international visibility and attractiveness of UTARTU, and contribute to the cosmic web studies and understanding of galaxy evolution.

Period: 01.01.2024—31.12.2030

PI (University of Tartu): Prof. Elmo Tempel

Funder: Ministry of Education and Research (Estonia)
Total Funding: 636 363 eur

The discovery of gravitational waves (GWs) opens novel possibilities to probe the foundations of our Universe in an attempt to go beyond current paradigms. The Centre of Excellence (CoE) “Foundations of the Universe” offers interdisciplinary research aimed at cross-correlating the results of GW observations with ongoing theoretical and experimental efforts in cosmology, particle physics and gravity. The CoE combines Estonian expertise in the mentioned fields and provides a unified framework that promotes interdisciplinary cooperation. Besides fundamental research, the proposed activities involve the development of experimental hardware and info-technology methods to extend current capabilities, including next-generation machine learning algorithms and the potential applications of quantum computers in fundamental research. The CoE relies on Estonian membership in ESA and CERN to boost knowledge transfer and cooperation with industry and raise the international competitiveness and awareness of Estonian science.
Prof. Elmo Tempel is leading the Astronomy workgroup in the CoE, whose main goal is to provide observational cosmic web competence.

Period: 01.01.2021—31.12.2025

PI: Prof. Elmo Tempel

Funder: Estonian Research Council
Total Funding: 1 225 000 EUR

<a title=”” href=”https://www.etis.ee/Portal/Projects/Display/fdc6716a-36c4-4c5a-9f68-da75fa98362f” target=”_blank” rel=”noopener” data-url=”https://www.etis.ee/Portal/Projects/Display/fdc6716a-36c4-4c5a-9f68-da75fa98362f”>Project info in ETIS</a>

One of the main unsolved fundamental puzzles in astrophysics is the question of how galaxies form and evolve in the Universe. One of the challenges is to understand whether galaxy evolution is driven by nature or nurture, i.e. what is the relative importance of the cosmic web environment to the evolution of galaxies?
In this project, we will develop new mathematical methods to study the co-evolution of galaxies and the cosmic web. The developed methods will be applied to the currently available observational and simulated datasets, but a clear focus is also set on the new upcoming large galaxy surveys.
One of the next generation large galaxy surveys is the European Southern Observatory flagship large survey 4MOST, which observes Galactic and extra-Galactic objects simultaneously. Among many fascinating topics, 4MOST allows us to study the galaxy evolution in the cosmic web environment with unprecedented details and from angles never possible before. We will take full advantage of this opportunity.

Period: 01.03.2016—01.03.2023

PI (University of Tartu): Prof. Elmo Tempel

Funder: Archimedes Foundation (Estonia)
Total Funding: 1 146 376 EUR

Recent measurements show that dark matter and dark energy yield 95% of the energy content of the Universe. Despite the extensive experimental effort, the nature, properties and origin of this dark sector remain concealed. The current paradigm portrays dark matter as a relic density of weakly interacting massive particles. Whereas the planned next-generation dark matter direct and indirect detection experiments, as well as the LHC, may still validate this picture, it is necessary to prepare for possible different outcomes. In this new perspective, the dark sector may potentially be as complicated as the visible sector, consisting of different types of particles and governed by nontrivial dark interactions. This CoE aims to explore the consequences of an interacting dark sector considering both conventional and nonconventional models of new physics, and studying its possible experimental signatures within particle physics, astroparticle physics and cosmology in an exhaustive way.

Period: 01.01.2015—31.12.2020

PI: Prof. Elmo Tempel

Funder: Estonian Research Council
Total Funding: 766 440 EUR

Galactic filaments are the most stringent structures found in nature, containing nearly half of the mass of the Universe. This proposal concentrates on the quantification of the galactic filaments. For the filament identification, we will use a novel probability-based filament finder, the Bisous model. Further development of the model would potentially give us a supreme structure finder for observational datasets that can be adapted to detect structures with any morphologies. Filaments (their shape, connectivity, concentration etc.) identified in galaxy surveys are a potentially rich source of astrophysical and cosmological information. We will use the filaments to study the nature of structure formation and dark energy, as well as the impact of filaments on the formation and evolution of galaxies with them. We will take advantage of the latest observational datasets and we will use numerical simulations to study the cosmological and astrophysical implications of filaments in the cosmic web.