This is a joint seminar of the Center for Advanced Studies at Skoltech and International laboratory for Mirror Symmetry and Automorphic Forms offered by myself in the 2019-2020 academic year. The lectures are scheduled on **Wednesday 19:00, room 249, Skoltech (1 Nobel Street, red building; public transport)**.

Automorphic forms serve as a systematic common generalization of various diverse objects such as Hecke characters and modular (or Hilbert, Mass, Siegel, ...) forms. They appear in number theory, representation theory, topology, harmonic analysis and mathematical physics. Most prominently, automorphic forms conjecturally provide a representation-theoretic style description of Galois representations of local and global fields via Langlands correspondence. Although Langlands conjectures are only partially proved at the moment, there are plenty of unconditional results purely on the automorphic side, interesting in their own right. In this seminar we will study these results and some known cases of Langlands correspondence.

During the first part of the course we will concentrate on the basic structure theory of complex automorphic forms and representations. In the second part we will move on to a more advanced topics and arithmetic applications, such as the local Langlands correspondence for $\mathrm{GL}_n$ and $p$-adic automorphic forms (if we have enough time).

- Reminder of the class field theory.
#### Complex automorphic representations

- Double adelic quotients, approximation theorems, Hecke algebra, Satake isomorphism, Bernstein decomposition.
- Admissible representations, Whittaker models, multiplicity one theorem, Flath's theorem.
- Eisenstein series.
- Arthur-Selberg trace formula.
- Jacquet-Langlands correspondence.
- Shimura varieties.
- $p$-divisible groups and their deformations, Lubin-Tate spaces.
- Etale cohomology of rigid analytic spaces.
- Langlands-Kottwitz method.
- Local Langlands for $\mathrm{GL}_n$.

Talk | Speaker | Date, place |
---|---|---|

Overview of the course | Artem Prikhodko | September, 18 |

Local class field theory | Gleb Terentiuk | September, 25 |

Global class field theory I | Dmitrii Krekov | October, 2 |

Global class field theory II | Dmitrii Krekov | October, 5 |

Structure theory of reductive groups, approximation theorems | Pavel Popov | October, 9 |

Smooth and admissible representations, Hecke algebra | Artem Prikhodko | October, 16 |

Skipped due to my graduation | October, 23 | |

Cuspidal representations, Bernstein decomposition | Artem Prikhodko | October, 30 |

Geometric Satake equivalence | Ivan Perunov | November, 6 |

Aside: higher traces and fixed point theorems | Artem Prikhodko | November, 13 |

Witt vector affine Grassmannian | Ivan Perunov | November, 20 |

Satake equivalence in mixed chacteristic | Ivan Perunov | November, 27 |

Aside: non-commutative Hodge-to-de Rham degeneration | Andrei Konovalov | December, 4 |

Traces and shtukas I | Roman Kositsin | December, 11 |

Traces and shtukas II | Roman Kositsin | December, 18 |

New year's talk: Frobenius action on commutative algebras and refined Mandell's theorem | Nikolai Konovalov | December, 25 |

Matsushima formula I | Vasya Rogov | January, 22 |

Matsushima formula II | Vasya Rogov | January, 29 |

Flath theorem | Alexander Novikov | February, 5 |

Whittaker models and Multiplicity One theorem | Artem Prikhodko | February, 12 |

Automorphic $L$-functions | Artem Prikhodko | February, 19 |

Skipped | February, 26 | |

Etale cohomology of rigid-analytic varieties I | Dmitrii Krekov | March, 4 |

Etale cohomology of rigid-analytic varieties II | Dmitrii Krekov | March, 11 |

Skipped | March, 18 | |

Jacquet-Langlands correspondence I | Artem Prikhodko | March, 25 |

Jacquet-Langlands correspondence II | Artem Prikhodko | April, 1 |

Cartier-Dieudonne theory of $\pi$-divisible groups | Artem Prikhodko | April, 15 |

Aside: Tannakian reconstruction in derived algebraic geometry | Artem Prikhodko | May, 6 |

Dieudonne-Manin classification | Alexander Novikov | May, 13 |

Deformation spaces of $\pi$-divisible groups | Artem Prikhodko | May, 20 |

Jacquet-Langlands III: two towers I | Artem Prikhodko | May, 28 |

Jacquet-Langlands III: two towers II | Artem Prikhodko | June, 4 |

Aside: Drinfeld's approach to prisms | Kirill Magidson | June, 18 |

- Sam Raskin, Lecture notes on cohomological class field theory (notes by Oron Propp).
- Ivan Losev, Vasia Krylov, Lecture notes on reductive groups and category O.
- Stephen Gelbart, Automorphic Forms on Adele Groups.
- Jayce R. Getz, An introduction to automorphic representations.
- James W. Cogdell, Lectures on $L$-functions, Converse Theorems, and Functoriality for $\mathrm{GL}_n$.
- Joseph Bernstein, Representations of p-adic groups.
- Michael Harris, An Introduction to the Stable Trace Formula.
- Alexandu Ioan Badulescu, The Jacquet-Langlands correspondence.
- Xinwen Zhu, An introduction to affine Grassmannians and the geometric Satake equivalence.
- Xinwen Zhu, Affine Grassmannians and the geometric Satake in mixed characteristic.
- Bhargav Bhatt, Peter Scholze, Projectivity of the Witt vector affine Grassmannian.
- Pierre Deligne, Travaux de Shimura.
- Alain Genestier, Bao Chau Ngo, Lectures on Shimura varieties.
- Torsten Wedhorn, The Local Langlands Correspondence for GL(n) over p-adic Fields.
- Robert E. Kottwitz, Points on some Shimura varieties over finite fields.
- Michael Harris, Richard Taylor, The geometry and cohomology of some simple Shimura varieties.
- Peter Scholze, The Langlands-Kottwitz approach for the modular curve and The Langlands-Kottwitz approach for some simple shimura varieties.
- Peter Scholze, The local langlands correspondence for $\mathrm{GL}_n$ over $p$-adic fields.
- Armand Borel, Nolan R. Wallach, Continuous Cohomology, Discrete Subgroups, and Representations of Reductive Groups.
- Matthew Emerton, On the interpolation of systems of eigenvalues attached to automorphic Hecke eigenforms.
- Matthew Emerton, A new proof of a theorem of Hida.
- Eric Urban, Eigenvarieties for reductive groups.
- Peter Scholze, On torsion in the cohomology of locally symmetric varieties.
- A. Caraiani, D. R. Gulotta, C.-Y. Hsu, C. Johansson, L Mocz, E. Reinecke, S.-C. Shih, Shimura varieties at level $\Gamma_1(p^\infty)$ and Galois representations.