# The Theory of Causal Fermion Systems

## Events

Here you find information on conferences, workshops and seminar talks related to causal fermion systems.

## Working Seminar "Mathematical Physics" in the Winter Term 2021/22

The seminar takes place in a mixed format, both in the lecture room and via Zoom. If you would like to attend the talks, please let us know via e*mail*. We will send you the Meeting-ID and password.

- Thursday, October 21, 2021, at 8:30 (always German time):
*Magdalena Lottner*, Universität Regensburg, tba - Friday, October 22, 2021, at 14:30
- Thursday, October 28, 2021, at 8:30
- Friday, October 29, 2021, at 14:30
- Thursday, November 4, 2021, at 8:30
- Friday, November 5, 2021, at 14:30
- Thursday, November 11, 2021, at 8:30
- Friday, November 12, 2021, at 14:30
- Thursday, November 18, 2021, at 8:30
- Friday, November 19, 2021, at 14:30
*Jeff Jauregui*, Union College, tba - Thursday, November 25, 2021, at 8:30
- Friday, November 26, 2021, at 14:30
*Demetre Kazaras*, Duke University, tba - Thursday, December 2, 2021, at 8:30
- Friday, December 3, 2021, at 14:30
*Gandalf Lechner*, Universität Erlangen, tba - Thursday, December 9, 2021, at 8:30
- Friday, December 10, 2021, at 14:30:
*Christian Hainzl*, LMU München, tba - Thursday, December 16, 2021, at 8:30
- Friday, December 17, 2021, at 14:30

## Past Events

## Working Seminar "Mathematical Physics" in the Summer Term 2021

The seminar takes place online via Zoom. If you would like to attend the talks, please let us know via e*mail*. We will send you the Meeting-ID and password.

- Thursday, April 15, 2021, at 8:30 (always German time): YouTube
*Felix Finster,*Universität Regensburg, “Baryogenesis in causal fermion systems: The adiabatic projection of the regularization” - Friday, April 16, 2021, at 14:30: YouTube
*Klaus Sibold*, Universität Leipzig, “Perturbative quantization of Einstein-Hilbert gravity” - Thursday, April 22, 2021, at 8:30:
*Marco Oppio*, Universität Regensburg, “Hölder continuity of the integrated causal Lagrangian in Minkowski space II” - Friday, April 23, 2021, at 14:30: YouTube, Slides
*Peter Schupp*, Jacobs University, Bremen, “Graded geometry and gravity” - Thursday, April 29, 2021, at 8:30:
*Magdalena Lottner*, Universität Regensburg, “Elliptic estimates for static causal fermion systems” - Friday, April 30, 2021, at 14:30: YouTube
*Rainer Verch*, Universität Leipzig, “Temperature and entropy-area relation of quantum matter near spherically symmetric outer trapping horizons” - Thursday, May 6, 2021, at 8:30: YouTube, Slides
*Thomas Schücker*, Aix-Marseille Université, “Minimal symmetry breaking of the cosmological principle and dominating dust” - Friday, May 7, 2021, at 14:30: YouTube, Slides
*Bernard Kay*, University of York, “A product picture for quantum electrodynamics” - Thursday, May 13, 2021: holiday, no talk!
- Friday, May 14, 2021, at 14:30: YouTube, Slides
*Jürg Fröhlich*, ETH Zürich, “Quantum dynamics of systems under repeated observation” - Thursday, May 20, 2021, at 8:30: YouTube
*Christoph Langer*, Universität Regensburg, “The Euler-Lagrange equations of the homogeneous causal variational principle II” - Friday, May 21, 2021, at 14:30: YouTube
*Daniele Oriti*, Ludwig-Maximilians-Universität München, “Tensorial group field theories: quantum geometry and emergent cosmology” - Thursday, May 27, 2021, at 8:30:
*Felix Finster*, Universität Regensburg, “On the causal fermion system describing the standard model” - Friday, May 28, 2021, at 14:30: YouTube, Slides
*Niky Kamran*, McGill University, Montréal, “Ramified local isometric embeddings of singular Riemannian metrics” - Thursday, June 3, 2021: holiday, no talk!
- Friday, June 4, 2021, at 14:30: YouTube, Slides
*Stefan Teufel*, Universität Tübingen, “Adiabatic theorems and linear response in the thermodynamic limit” - Thursday, June 10, 2021, at 8:30:
*Maximilian Jokel*, Universität Regensburg, “Inverting the Second Variation of the Regularized Causal Action” - Friday, June 11, 2021, at 14:30: YouTube, Slides
*Klaas Landsman*, Radboud University, Nijmegen, “Quantization: The big picture” - Thursday, June 17, 2021, at 8:30:
*Marco Oppio*, Universität Regensburg, “An algebraic model for causal fermion systems” - Thursday, June 24, 2021, at 8:30:
*Saeed Zafari*, Universität Regensburg, “Circumference and Gauß curvature for causal fermion systems in spin dimension one” - Friday, June 25, 2021, at 14:30: YouTube, Slides
*Miguel Manzano*, Universidad de Salmanca, “Null shells: general matching across null boundaries and connection with cut-and-paste formalism” - Thursday, July 1, 2021, at 8:30:
*Johannes Wurm*, Universität Regensburg, “On the area constraint for the mass of time-dependent spacetimes” - Friday, July 2, 2021, at 14:30:
**13th Colloquium****“Mathematics and Foundations of Quantum Theory”**jointly with Dirk Deckert (München), Peter Pickl (Tübingen) and Wojciech Dybalski (Poznan)- 15:00
*Sergio Albeverio*and*Francesco De Vecchi*, Universität Bonn:

“Stochastic methods in quantum fields: introduction and applications to scalar fields” - 16:30
*Massimiliano Gubinelli*, Universität Bonn:

“Some aspects of the stochastic quantisation of the $\phi^4_3$ model”

- 15:00
- Thursday, July 8, 2021, at 8:30:
*Michelle Frankl*, Universität Regensburg, “Causal variational principles in the homogeneous setting: The Euler-Lagrange equations in the compact case” - Friday, July 9, 2021, at 14:30: YouTube, Slides
*Robert Oeckl*, UNAM Morelia, “alpha-Kähler quantization” - Thursday, July 15, 2021, at 8:30:
*Tobias Butzmann*, Universität Regensburg, “Causal fermion systems with symmetries” - Friday, July 16, 2021, at 14:30: YouTube, Slides
*Moritz Reintjes*, Universität Konstanz, “Uhlenbeck compactness and optimal regularity in Lorentzian geometry and for Yang-Mills gauge theories” - Friday, July 23, 2021, at 14:30: YouTube, Slides
*Kasia Rejzner*, University of York, “C$^*$-algebraic formulation of interacting quantum field theory applied to fermions“

## Working Seminar "Mathematical Physics" in the Winter Term 2020/21

The seminar took place online via Zoom.

- Friday, October 23, 2020, at 14:30 (always German time): YouTube
*José M. Isidro*, Universidad Politécnica de Valencia, “An introduction to the chiral anomaly” - Friday, November 6, 2020, at 15:00: YouTube, Slides
*Michael Kiessling*, Rutgers University, “On the general-relativistic quantum-mechanical spectrum of hydrogenic ions” - Thursday, November 12, 2020, at 8:30:
*Magdalena Lottner*, Universität Regensburg, “The chain rule for causal fermion systems in the infinite-dimensional setting and Hölder continuity of the causal Lagrangian” - Friday, November 13, 2020, at 14:30: YouTube, Notes
*Felix Finster*, Universität Regensburg, “A mechanism for baryogenesis in causal fermion systems” - Thursday, November 19, 2020, at 8:30:
*Marco Oppio*, Universität Regensburg, “Hölder continuity of the integrated causal Lagrangian in Minkowski space” - Friday, November 20, 2020, at 14:30: YouTube, Slides
*Claudio Paganini*, Universität Regensburg and Albert-Einstein-Institut, Potsdam, “Incompatibility of frequency splitting and spatial localization: A quantitative analysis of Hegerfeldt’s theorem” - Thursday, November 26, 2020, at 8:30:
*Christoph Langer*, Universität Regensburg, “The Euler-Lagrange equations of the homogeneous causal variational principle” - Friday, November 27, 2020, at 14:30: Video
*Eduardo Guendelman*, Ben Gurion University, “Non-canonical volume-form formulation of modified gravity theories and cosmology“ - Thursday, December 3, 2020, at 8:30: YouTube
*Felix Finster*, Universität Regensburg, “A definition of entropy for causal fermion systems” - Friday, December 4, 2020, at 14:30: YouTube, Slides
*Wolfgang Spitzer*, Fernuniversität Hagen, “Entanglement entropy of the ideal Fermi gas” - Thursday, December 10, 2020, at 8:30:
*Maximilian Jokel*, Universität Regensburg, “Second variations of the causal action and baryogenesis” - Friday, December 11, 2020, at 14:30: YouTube
*Felix Finster*, Universität Regensburg, “The quantum state induced by the universal measure” - Thursday, December 17, 2020, at 8:30:
*Saeed Zafari*, Universität Regensburg, “The curvature of the Dirac sphere” - Thursday, January 7, 2021, at 8:30: YouTube
*Felix Finster,*Universität Regensburg, “Baryogenesis in causal fermion systems: Conservation laws and scalings” - Friday, January 8, 2021, at 14:30: YouTube
*Christoph Langer*, Universität Regensburg, “Causal variational principles in the infinite-dimensional setting: Existence of minimizers” - Thursday, January 14, 2020, at 8:30: YouTube, Slides
*Christoph Krpoun*, Humboldt-Universität zu Berlin, “The Dirac equation and its separation in the Reissner-Nordström geometry” - Friday, January 15, 2021, at 14:30: YouTube
*Peter Müller*, LMU München, “Entanglement entropy for quasi-free Fermi gases” - Thursday, January 21, 2021, at 8:30:
*Johannes Wurm*, Universität Regensburg, “On the definition of the total mass for causal fermion systems” - Friday, January 22, 2021, at 14:30: YouTube
*Albert Much*, Universität Leipzig, “Strict deformation quantization in curved spacetimes” - Thursday, January 28, 2021, at 8:30: YouTube
*Felix Finster,*Universität Regensburg, “Baryogenesis in causal fermion systems: The dynamics of the regularization” - Friday, January 29, 2021, at 14:30: YouTube, Slides
, Universität Leipzig, “Trace anomaly for chiral fermions”

Sami Abdallah - Thursday, February 4, 2021, at 8:30: YouTube, Slides
*Christiaan van de Ven,*Università di Trento, “Asymptotic equivalence of two strict deformation quantizations and applications to the classical limit” - Friday, February 5, 2021:
**Colloquium****“Mathematical Physics Regensburg-Munich”**jointly with LMU and TU Munich (co-organized with Dirk Deckert, Wojciech Dybalski and Peter Pickl)- 13:00
*Roderich Tumulka*, Universität Tübingen: YouTube, Slides

“Multi-time version of the Landau-Peierls formulation of quantum electrodynamics” - 14:30
*Felix Finster*, Universität Regensburg: YouTube, Slides

“Quantum states of causal fermion systems and collapse”

- 13:00
- Friday, February 12, 2021, at 14:30: YouTube
*Eric Ling*, Rutgers University, “Spacetime extensions of the big bang” - Thursday, February 25, 2021, at 8:30:
*Magdalena Lottner*, Universität Regensburg, “Towards an area law for the Klein-Gordon projector” - Friday, February 26, 2021, at 14:30: YouTube
*Claudio Paganini*, Universität Regensburg and Albert-Einstein-Institut, Potsdam, “Ideas on baryogenesis”

## Working Seminar "Mathematical Physics" in the Summer Term 2020

The seminar took place online via Zoom.

- Thursday, April 24, 2020, at 8:30 (always German time):
*Felix Finster*, Universität Regensburg, “The nonlinear surface layer integral and the symmetrized Fock norm I” - Thursday, April 30, 2020, at 14:30:
*Felix Finster*, Universität Regensburg, “The nonlinear surface layer integral and the symmetrized Fock norm II” - Thursday, May 7, 2020, at 14:30:
*Felix Finster*, Universität Regensburg, “Extending the commutator inner product in a surface layer” - Friday, May 15, 2020, at 14:30: YouTube
*Saeed Zafari and Felix Finster*, Universität Regensburg, “Towards a Gauß-Bonnet theorem for causal fermion systems” - Friday, May 22, 2020 at 14:30:
*Claudio Paganini*, Universität Regensburg and Albert-Einstein-Institut, Potsdam, “The ETH formulation of quantum theory I” - Friday, May 29, 2020, at 14:30:
*Magdalena Lottner*, Universität Regensburg, “Entanglement entropy in the context of causal fermion systems” - Friday, June 5, 2020 at 14:30:
*Simone Murro*, Università di Trento, “On the Cauchy problem for symmetric hyperbolic systems on globally hyperbolic manifolds with timelike boundary” - Friday, June 12, 2020 at 14:30: YouTube
*Felix Finster*, Universität Regensburg, “Energy estimates and cone structures for the linearized field equations” - Friday, June 19:

No talk because of**LQP Workshop**(see below) - Friday, June 26, 2020 at 14:30: YouTube
*Miguel Sánchez Caja*, Universidad de Granada, “Some techniques related to Causality and Global Hyperbolicity” - Friday, July 3, 2020:
**Colloquium****“Mathematical Physics Regensburg-Munich”**jointly with LMU and TU Munich (co-organized with Dirk Deckert, Wojciech Dybalski and Peter Pickl)- 13:00
*Jens Mund*, Universidade Federal de Juiz de Fora and TU München, “Perturbative construction of a string-localized Dirac field in a Hilbert space representation of QED” - 14:30
*Claudio Dappiaggi*, Università degli Studi di Pavia, “Boundary conditions for Maxwell’s equations on globally hyperbolic spacetimes with timelike boundary”

- 13:00
- Friday, July 10, 2020:
**Colloquium****“Mathematical Physics Regensburg-Munich”**jointly with LMU and TU Munich (co-organized with Dirk Deckert, Wojciech Dybalski and Peter Pickl)- 13:00
*Vincenzo Morinelli*, Università degli Studi di Roma `Tor Vergata’, “Covariant homogeneous nets of standard subspaces” - 14:30
*Nicola Pinamonti*, Università di Genova, “Existence and uniqueness of solutions of the semiclassical Einstein equation in cosmology“

- 13:00
- Friday, July 17, 2020:
- 13:00
*Harald Grosse,*Universität Wien, “A solvable noncommutative Quantum Field Theory” - 14:30
*Claudio Paganini*, Universität Regensburg and Albert-Einstein-Institut, Potsdam, “The ETH formulation of quantum theory II”

- 13:00
- Friday, July 24, 2020 at 14:30:
*Marco Oppio*, Universität Regensburg, “Symmetrized nonlinear surface layer integrals: An example in Minkowski space”

## Seminar talks at Universität Tübingen, July 8 and 9, 2020

- Wednesday, 8 July 2020 (online via Zoom): YouTube, Slides
*Felix Finster*, Universität Regensburg, “Causal fermion systems and the causal action principle” - Thursday, 9 July 2020 (online via Zoom): YouTube, Slides
*Felix Finster*, Universität Regensburg, “A positive mass theorem for static causal fermion systems”

## First Virtual LQP Workshop, June 17-19, 2020

The workshop took place online. For details see the conference website.

*Magdalena Lottner*gave a talk on “Entropy in causal fermion systems” on June 19 at 14:20 British summer time (i.e. 15:20 local time in Germany).

*More information on past events can be found on the research page of Felix Finster at Universität Regensburg.*