The Cosmic Web and its impact on galaxy formation and alignment

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Galaxies are the most fundamental building blocks of the Universe. Observations have shown that they are not randomly distributed throughout the cosmos, but are organised in a complex filamentary pattern: the Cosmic Web. This is the stage on which galaxies gain their gas, angular momentum and merge with smaller satellites galaxies. Accordingly, they exhibit different levels of geometric and kinematic alignment. In our local universe, the satellite galaxies of the Milky Way (and our neighbours the Andromeda galaxy M31 and Centaurus A) sit on thin, co-rotating planes. Such a spatial configuration is difficult to obtain in the current 'Lambda Cold Dark Matter' cosmology. How did such alignment originate? Are they a challenge to our paradigm of how structures and galaxies form? On even larger scales, galaxies throughout the cosmic web are mutually aligned with each other. Increasing evidence points to an intimate relationship between galaxies and the cosmic web. In this project we intend to use both local constrained simulations and semi-analytical models to examine the impact of the cosmic web on galaxy alignment. Such a study will help us understand if the peculiar configuration of satellites seen in the local volume is unique as well as gain insight into the alignment on various scales. The complementarity of our expertise will drive the project forwards: while the Chinese side brings expertise of galaxy modelling the German side brings experience in simulating the local volume. Together we also aim to enhance our existing sino-german collaboration and to train the next generation of galaxy astrophysicists.