activity
20132026
most citedActive crystals on a sphere

54 citations · 414 across the 19 of their papers we have counts for

collaborators

20 papers

math.NA2026

Odd behaviour of even geometries: an explanation for superconvergent geometric consistency errors

Hanne Hardering, Simon Praetorius, Gentian Zavalani

Piecewise polynomial surface approximations used in surface finite element methods often seem to behave better than their standard approximation properties suggest if their polynom…

math.NA2025

Surface Minkowski tensors to characterize shapes on curved surfaces

Lea Happel, Hanne Hardering, Simon Praetorius +1

We introduce surface Minkowski tensors to characterize rotational symmetries of shapes embedded in curved surfaces. The definition is based on a modified vector transport of the sh…

cond-mat.soft2023★ 3 cited

Active smectics on a sphere

Michael Nestler, Simon Praetorius, Zhi-Feng Huang +2

The dynamics of active smectic liquid crystals confined on a spherical surface is explored through an active phase field crystal model. Starting from an initially randomly perturbe…

math.NA2023★ 4 cited

Parametric Finite Element Discretization of the Surface Stokes Equations

Hanne Hardering, Simon Praetorius

We study a higher-order surface finite element (SFEM) penalty-based discretization of the tangential surface Stokes problem. Several discrete formulations are investigated which ar…

physics.flu-dyn2022★ 4 cited

The influence of finite size particles on fluid velocity and transport though porous media

Mirko Residori, Simon Praetorius, Pietro de Anna +1

Understanding the coupling between flow, hydrodynamic transport and dispersion of colloids with finite-size in porous media is a long-standing challenge. This problem is relevant f…

math.NA2022★ 3 cited

Diffusion of tangential tensor fields: numerical issues and influence of geometric properties

Elena Bachini, Philip Brandner, Thomas Jankuhn +4

We study the diffusion of tangential tensor-valued data on curved surfaces. For this purpose, several finite-element-based numerical methods are collected and used to solve a tange…

math.NA2021★ 16 cited

Tangential Errors of Tensor Surface Finite Elements

Hanne Hardering, Simon Praetorius

We discretize a tangential tensor field equation using a surface-finite element approach with a penalization term to ensure almost tangentiality. It is natural to measure the quali…

math.NA2021★ 37 cited

Finite element discretization methods for velocity-pressure and stream function formulations of surface Stokes equations

Philip Brandner, Thomas Jankuhn, Simon Praetorius +2

In this paper we study parametric TraceFEM and parametric SurfaceFEM (SFEM) discretizations of a surface Stokes problem. These methods are applied both to the Stokes problem in vel…

cs.MS2020★ 18 cited

Dune-CurvedGrid -- A Dune module for surface parametrization

Simon Praetorius, Florian Stenger

In this paper we introduce and describe an implementation of curved (surface) geometries within the Dune framework for grid-based discretizations. Therefore, we employ the abstract…

physics.comp-ph2019★ 20 cited

An efficient numerical framework for the amplitude expansion of the phase-field crystal model

Simon Praetorius, Marco Salvalaglio, Axel Voigt

The study of polycrystalline materials requires theoretical and computational techniques enabling multiscale investigations. The amplitude expansion of the phase field crystal mode…

cond-mat.soft2018★ 21 cited

Topological and geometrical quantities in active cellular structures

Dennis Wenzel, Simon Praetorius, Axel Voigt

Topological and geometrical properties and the associated topological defects find a rapidly growing interest in studying the interplay between mechanics and the collective behavio…

cond-mat.soft2018★ 54 cited

Active crystals on a sphere

Simon Praetorius, Axel Voigt, Raphael Wittkowski +1

Two-dimensional crystals on curved manifolds exhibit nontrivial defect structures. Here, we consider "active crystals" on a sphere, which are composed of self-propelled colloidal p…

cond-mat.soft2017★ 25 cited

Nematic liquid crystals on curved surfaces - a thin film limit

Ingo Nitschke, Michael Nestler, Simon Praetorius +2

We consider a thin film limit of a Landau-de Gennes Q-tensor model. In the limiting process we observe a continuous transition where the normal and tangential parts of the Q-tensor…

math.NA2016★ 50 cited

Orientational order on surfaces - the coupling of topology, geometry, and dynamics

Michael Nestler, Ingo Nitschke, Simon Praetorius +1

We consider the numerical investigation of surface bound orientational order using unit tangential vector fields by means of a gradient-flow equation of a weak surface Frank-Oseen…

cond-mat.soft2016★ 37 cited

A mesoscopic field theoretical approach for active systems

Francesco Alaimo, Simon Praetorius, Axel Voigt

We introduce a mesocopic modeling approach for active systems. The continuum model allows to consider microscopic details as well as emerging macroscopic behavior and can be consid…

physics.comp-ph2015★ 23 cited

Development and Analysis of a Block-Preconditioner for the Phase-Field Crystal Equation

Simon Praetorius, Axel Voigt

We develop a preconditioner for the linear system arising from a finite element discretization of the Phase Field Crystal (PFC) equation. The PFC model serves as an atomic descript…

cond-mat.soft2015★ 1 cited

Liquid crystalline growth within a phase-field crystal model

Sai Tang, Simon Praetorius, Rainer Backofen +3

By using a phase-field crystal (PFC) model, the liquid-crystal growth of the plastic triangular phase is simulated with emphasis on crystal shape and topological defect formation.…

q-bio.CB2014★ 53 cited

A mechanism for cell motility by active polar gels

Wieland Marth, Simon Praetorius, Axel Voigt

We analyse a generic motility model, with the motility mechanism arising by contractile stress due to the interaction of myosin and actin. A hydrodynamic active polar gel theory is…

cond-mat.soft2013★ 33 cited

A Navier Stokes Phase Field Crystal Model for Colloidal Suspensions

Simon Praetorius, Axel Voigt

We develop a fully continuous model for colloidal suspensions with hydrodynamic interactions. The Navier Stokes Phase Field Crystal (NS-PFC) model combines ideas of dynamic density…

cond-mat.soft2013★ 12 cited

Structure and dynamics of interfaces between two coexisting liquid crystalline phases

Simon Praetorius, Axel Voigt, Raphael Wittkowski +1

The phase-field-crystal model is used to access the structure and thermodynamics of interfaces between two coexisting liquid crystalline phases in two spatial dimensions. Depending…