Abstract
In this work, we study the supersingular locus of the Shimura variety associated to the unitary group
Funding source: European Research Council
Award Identifier / Grant number: 770936
Funding source: Deutsche Forschungsgemeinschaft
Award Identifier / Grant number: 390685587
Award Identifier / Grant number: 444845124
Funding statement: I was supported by the ERC Consolidator Grant 770936: NewtonStrat, by the Ada Lovelace Fellowship of the Cluster of Mathematics Münster funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy EXC 2044 – 390685587, Mathematics Münster: Dynamics-Geometry-Structure, and by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) through the Collaborative Research Center TRR326 “Geometry and Arithmetic of Uniformized Structures”, project number 444845124.
A The Gröbner basis of Proposition 2.6
We list here the polynomials of the Gröbner basis 𝐺 used in the proof of Proposition 2.6.
To make the notation more readable and the lexicographic order more intuitive, we have substituted the variables
The monomial order is then simply the usual alphabetical order.
We list here the elements of the Gröbner basis used in the proof of Proposition 2.6 and already divide them into the subsets
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B Code for Chapter 2
The following script can be run in SageMath [52] and produces the Gröbner basis above together with the computations needed in the proof of Proposition 2.6. One can slightly modify the matrix in the beginning to adapt the code to higher dimension 𝑛. We caution the reader that the function for computing the set of unlucky primes, in the sense of Proposition 2.13, is highly inefficient. Especially, the last part of this code requires about one day running time on a laptop.
C Code for Chapter 7
The following script can be run in SageMath [52] and produces the list of admissible elements for the group-theoretical datum
Acknowledgements
First and foremost, I would like to thank my supervisor Eva Viehmann for her support during my PhD. I am sincerely thankful for her constant help and feedback, which guided me through my studies. I wish to express my gratitude to Michael Rapoport and Torsten Wedhorn for very helpful discussions and for answering my questions on their papers [41, 48]. I am thankful to Felix Schremmer for sharing his knowledge on Coxeter groups and affine Deligne–Lusztig varieties, pointing me to the relevant literature for Section 4. I would like to thank Simone Ramello for introducing me to model theory and working out together the details of Remark 2.16. I am also grateful to Urs Hartl and Damien Junger for helpful conversations.
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- No compact split limit Ricci flow of type II from the blow-down
- Deriving Perelman’s entropy from Colding’s monotonic volume
- Gravitational instantons with 𝑆1 symmetry
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- On the Rapoport--Zink space for GU(2, 4) over a ramified prime
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Articles in the same Issue
- Frontmatter
- No compact split limit Ricci flow of type II from the blow-down
- Deriving Perelman’s entropy from Colding’s monotonic volume
- Gravitational instantons with 𝑆1 symmetry
- Relatively Anosov groups: finiteness, measure of maximal entropy, and reparameterization
- On the Rapoport--Zink space for GU(2, 4) over a ramified prime
- Generalized Jouanolou duality, weakly Gorenstein rings, and applications to blowup algebras
- On polynomial convergence to tangent cones for singular Kähler–Einstein metrics
- Anomaly flow: Shi-type estimates and long-time existence