Fischer Group
Theory of Partial Differential Equations, Applied and Numerical Analysis
Diverse phenomena such as the motion of fluids or elastic objects, the evolution of interfaces, or the physics of quantum-mechanical particles are described accurately by partial differential equations. The Fischer group works on the mathematical analysis of partial differential equations that arise in the sciences, connecting also to areas like numerical analysis or probability.
Partial differential equations are a fundamental tool for the description of many phenomena in the sciences, ranging from the physics of continua like fluids or elastic solids over quantum mechanics to population biology. Julian Fischer and his group work on the mathematical aspects of partial differential equations. One of the group’s main themes is the mathematical justification of model simplifications: For example, an elastic material with a highly heterogeneous small-scale structure may in many cases be approximated as a homogeneous material. Likewise, a fluid with low compressibility may in many cases be approximated as ideally incompressible. To justify such approximations, the group derives rigorous estimates for the approximation error. The techniques they employ connect the analysis of PDEs with adjacent mathematical areas like numerical analysis and probability.
Team
Current Projects
Effective behavior of random materials | Evolution of interfaces in fluid mechanics and solids | Fluctuating hydrodynamics and SPDEs | Entropy-dissipative PDEs
Publications
Abels H, Fischer JL, Moser M. 2024. Approximation of classical two-phase flows of viscous incompressible fluids by a Navier–Stokes/Allen–Cahn system. Archive for Rational Mechanics and Analysis. 248(5), 77. View
Agresti A, Veraar M. 2024. Reaction-diffusion equations with transport noise and critical superlinear diffusion: Global well-posedness of weakly dissipative systems. SIAM Journal on Mathematical Analysis. 56(4), 4870–4927. View
Clozeau N, Wang L. 2024. Artificial boundary conditions for random elliptic systems with correlated coefficient field. Multiscale Modeling and Simulation. 22(3), 973–1029. View
Abels H, Fei M, Moser M. 2024. Sharp interface limit for a Navier–Stokes/Allen–Cahn system in the case of a vanishing mobility. Calculus of Variations and Partial Differential Equations. 63(4), 94. View
Agresti A, Veraar M. 2024. The critical variational setting for stochastic evolution equations. Probability Theory and Related Fields. 188, 957–1015. View
ReX-Link: Julian Fischer
Career
Since 2022 Professor, Institute of Science and Technology Austria (ISTA)
2017 – 2022 Assistant Professor, Institute of Science and Technology Austria (ISTA)
2014 – 2016 Postdoc, Max Planck Institute for Mathematics in the Sciences, Leipzig, Germany
2013 – 2014 Postdoc, University of Zurich, Switzerland
2013 PhD, University of Erlangen-Nürnberg, Germany
Selected Distinctions
2020 ERC Starting Grant
2020 ÖMG-Förderungspreis, Early-/Mid-Career-Award of the Austrian Mathematical Society
2015 Dr. Körper Prize, PhD Award of the GAMM
Additional Information
Open Julian Fischer’s website
Go to Mathphys Analysis Seminar website
Mathematics at ISTA