Zwicker Group
@zwickergroup.bsky.social
Theoretical biophysics group at MPI-DS, Göttingen. We study the spatiotemporal organization of soft matter in cells, tissues, and synthetic systems; see www.zwickergroup.org
Pinned
Zwicker Group
@zwickergroup.bsky.social
· Jan 24
We wrote a review on the "Physics of droplet regulation in biological cells": arxiv.org/abs/2501.13639 Beside the basic #physics of phase separation, we discuss three aspects that separate cellular from traditional droplets:
Reposted by Zwicker Group
"While the concept of condensates is successfully rewriting cell biology textbooks, there is some danger of overhype and backlash."
This workshop summary is great - particularly the idea to shift from "Is it a condensate?" to "what problem does that solve?"
but "successfully" stood out for me here
This workshop summary is great - particularly the idea to shift from "Is it a condensate?" to "what problem does that solve?"
but "successfully" stood out for me here
Physicists' perspective on the future direction of condensates in Cell Biology.
arxiv.org/abs/2601.03677
arxiv.org/abs/2601.03677
Roadmap for Condensates in Cell Biology
Biomolecular condensates govern essential cellular processes yet elude description by traditional equilibrium models. This roadmap, distilled from structured discussions at a workshop and reflecting t...
arxiv.org
January 8, 2026 at 11:15 AM
"While the concept of condensates is successfully rewriting cell biology textbooks, there is some danger of overhype and backlash."
This workshop summary is great - particularly the idea to shift from "Is it a condensate?" to "what problem does that solve?"
but "successfully" stood out for me here
This workshop summary is great - particularly the idea to shift from "Is it a condensate?" to "what problem does that solve?"
but "successfully" stood out for me here
Curtesy of @jerelleaj.bsky.social who was our amazing master of the black board!
January 8, 2026 at 10:36 AM
Curtesy of @jerelleaj.bsky.social who was our amazing master of the black board!
Our "Roadmap for Condensates in Cell Biology" is now available on arXiv: arxiv.org/abs/2601.03677 🎉 This article summarizes the interdisciplinary weekly discussions we had at our condensate workshop at KITP in the summer of 2025. Feedback is very welcome!
Roadmap for Condensates in Cell Biology
Biomolecular condensates govern essential cellular processes yet elude description by traditional equilibrium models. This roadmap, distilled from structured discussions at a workshop and reflecting t...
arxiv.org
January 8, 2026 at 7:33 AM
Our "Roadmap for Condensates in Cell Biology" is now available on arXiv: arxiv.org/abs/2601.03677 🎉 This article summarizes the interdisciplinary weekly discussions we had at our condensate workshop at KITP in the summer of 2025. Feedback is very welcome!
All the best, Aljaz!
December 30, 2025 at 3:02 PM
All the best, Aljaz!
We're looking for a postdoc to strengthen our group! Please apply by January 15, 2026 if you're a fun and motivated person who likes theoretical modeling of biological processes by combining analytics and numerics. There is freedom in choosing projects! Details: www.ds.mpg.de/4110032/job_...
December 17, 2025 at 12:39 PM
We're looking for a postdoc to strengthen our group! Please apply by January 15, 2026 if you're a fun and motivated person who likes theoretical modeling of biological processes by combining analytics and numerics. There is freedom in choosing projects! Details: www.ds.mpg.de/4110032/job_...
Our work helps us to understand the fundamental behaviors of chemically active droplets. We hope that it guides future understanding of biomolecular condensates and also experiments reconstituting these droplets in synthetic systems. Details are available in the pre-print: arxiv.org/abs/2512.02542
Size control guidelines for chemically active droplets
Biological cells and synthetic analogues use liquid-liquid phase separation to dynamically compartmentalize their environment for various applications. In many cases, multiple droplets need to coexist...
arxiv.org
December 15, 2025 at 8:07 AM
Our work helps us to understand the fundamental behaviors of chemically active droplets. We hope that it guides future understanding of biomolecular condensates and also experiments reconstituting these droplets in synthetic systems. Details are available in the pre-print: arxiv.org/abs/2512.02542
More generally, we identified that reactions can either take place in the entire droplet volume or just in a region limited to the interface. These two different classes of droplets behave qualitatively differently.
December 15, 2025 at 8:07 AM
More generally, we identified that reactions can either take place in the entire droplet volume or just in a region limited to the interface. These two different classes of droplets behave qualitatively differently.
Our simplest model describes a binary fluid, which exhibits phase separation and conversion of the two species into each other. Using linear non-equilibrium thermodynamics, we asked how different conversion rates affect droplet sizes, and this parameter dependence turned out to be complex.
December 15, 2025 at 8:07 AM
Our simplest model describes a binary fluid, which exhibits phase separation and conversion of the two species into each other. Using linear non-equilibrium thermodynamics, we asked how different conversion rates affect droplet sizes, and this parameter dependence turned out to be complex.
Since more than a decade, our group has been exploring chemically active droplets, which are exciting since their size can be controlled. Yet, we still do not fully understand this control even in the simplest models. Until a new preprint (arxiv.org/abs/2512.02542) spearheaded by postdoc Guido...
Size control guidelines for chemically active droplets
Biological cells and synthetic analogues use liquid-liquid phase separation to dynamically compartmentalize their environment for various applications. In many cases, multiple droplets need to coexist...
arxiv.org
December 15, 2025 at 8:07 AM
Since more than a decade, our group has been exploring chemically active droplets, which are exciting since their size can be controlled. Yet, we still do not fully understand this control even in the simplest models. Until a new preprint (arxiv.org/abs/2512.02542) spearheaded by postdoc Guido...
Congratulations, Anna! Welcome to this great program 🎉
December 2, 2025 at 5:31 PM
Congratulations, Anna! Welcome to this great program 🎉
Wow, congratulations!
November 27, 2025 at 2:07 PM
Wow, congratulations!
Reposted by Zwicker Group
📢 Paper alert 📢
Chirality is known to be important for the movement of microorganisms and active matter. In our new paper out today in @natphys.nature.com, we show that chirality is used by malaria parasites to control their motion patterns:
doi.org/10.1038/s415...
Here comes a 🧵 ... (1/9)
Chirality is known to be important for the movement of microorganisms and active matter. In our new paper out today in @natphys.nature.com, we show that chirality is used by malaria parasites to control their motion patterns:
doi.org/10.1038/s415...
Here comes a 🧵 ... (1/9)
November 24, 2025 at 5:50 PM
📢 Paper alert 📢
Chirality is known to be important for the movement of microorganisms and active matter. In our new paper out today in @natphys.nature.com, we show that chirality is used by malaria parasites to control their motion patterns:
doi.org/10.1038/s415...
Here comes a 🧵 ... (1/9)
Chirality is known to be important for the movement of microorganisms and active matter. In our new paper out today in @natphys.nature.com, we show that chirality is used by malaria parasites to control their motion patterns:
doi.org/10.1038/s415...
Here comes a 🧵 ... (1/9)
In contrast, short-range interactions (e.g., non-local elasticity and Riccardo's system discussed above) show various patterns, which can be explained by a mapping to the Swift-Hohenberg model. These results demonstrates that various processes arresting droplet coarsening fall into two categories.
November 24, 2025 at 9:45 AM
In contrast, short-range interactions (e.g., non-local elasticity and Riccardo's system discussed above) show various patterns, which can be explained by a mapping to the Swift-Hohenberg model. These results demonstrates that various processes arresting droplet coarsening fall into two categories.
Filipe's work (in collaboration with Yicheng and Oliver) puts these results in context by generally studying the influence of non-local interactions onto phase separation. We find that long-range interactions (e.g., electrostatics and also chemical reactions) generally suppress phase separation.
November 24, 2025 at 9:45 AM
Filipe's work (in collaboration with Yicheng and Oliver) puts these results in context by generally studying the influence of non-local interactions onto phase separation. We find that long-range interactions (e.g., electrostatics and also chemical reactions) generally suppress phase separation.
Active processes can further control the droplet dynamics. They can either accelerate coarsening, or they can suppress it completely. In the latter case, we also find interesting states where a macroscopic droplet coexists with a patterned phase comprising many smaller spots.
November 24, 2025 at 9:45 AM
Active processes can further control the droplet dynamics. They can either accelerate coarsening, or they can suppress it completely. In the latter case, we also find interesting states where a macroscopic droplet coexists with a patterned phase comprising many smaller spots.
Riccardo and Gerrit looked at condensates embedded in membranes, using polarity spots of yeast as an example. They showed that exchange with the bulk can strongly accelerate coarsening, allowing cells to form one spot quickly.
November 24, 2025 at 9:45 AM
Riccardo and Gerrit looked at condensates embedded in membranes, using polarity spots of yeast as an example. They showed that exchange with the bulk can strongly accelerate coarsening, allowing cells to form one spot quickly.
Two more pre-prints from the group 🎉 Riccardo explored how cells could control surface condensates by regulating bulk exchange (arxiv.org/abs/2511.03619). Filipe studied the impact of non-local interactions onto phase separation (arxiv.org/abs/2511.05214). Some more details in the thread:
November 24, 2025 at 9:45 AM
Two more pre-prints from the group 🎉 Riccardo explored how cells could control surface condensates by regulating bulk exchange (arxiv.org/abs/2511.03619). Filipe studied the impact of non-local interactions onto phase separation (arxiv.org/abs/2511.05214). Some more details in the thread:
No, I don’t agree with such a blanket statement. Equilibrium concepts can also be useful in non-equilibrium situations. For instance, phase coexistence may hold at the interface, while active processes modulate the bulk phases. I propose a more nuanced view, depending on the concrete system.
November 21, 2025 at 6:41 PM
No, I don’t agree with such a blanket statement. Equilibrium concepts can also be useful in non-equilibrium situations. For instance, phase coexistence may hold at the interface, while active processes modulate the bulk phases. I propose a more nuanced view, depending on the concrete system.
I don’t know the details of this paper, but one generally needs to be cautious. Phase separation can be a useful conceptual framework, but since cells are complex, it can rarely be „proven“.
November 21, 2025 at 6:30 PM
I don’t know the details of this paper, but one generally needs to be cautious. Phase separation can be a useful conceptual framework, but since cells are complex, it can rarely be „proven“.
Our review on the physics of phase separation in cells has been published by Rep. Prog. Phys. 🎉 doi.org/10.1088/1361...
We hope that the text and citations are helpful for anyone interested in physical descriptions of condensates in cells!
We hope that the text and citations are helpful for anyone interested in physical descriptions of condensates in cells!
November 21, 2025 at 5:57 PM
Our review on the physics of phase separation in cells has been published by Rep. Prog. Phys. 🎉 doi.org/10.1088/1361...
We hope that the text and citations are helpful for anyone interested in physical descriptions of condensates in cells!
We hope that the text and citations are helpful for anyone interested in physical descriptions of condensates in cells!
Another pre-print from our group see's the light of day! 🎉 This time we how the coarsening of droplets is affected by advection and reactions: arxiv.org/abs/2510.00827 @stefankoestler2025.bsky.social describes our surprising findings in the thread below ⤵️
October 2, 2025 at 12:43 PM
Another pre-print from our group see's the light of day! 🎉 This time we how the coarsening of droplets is affected by advection and reactions: arxiv.org/abs/2510.00827 @stefankoestler2025.bsky.social describes our surprising findings in the thread below ⤵️
Our latest work from a stimulating collaboration with @jerelleaj.bsky.social and @nathanieldhess.bsky.social is out now!
Out now in #ACSMacroLett: we demonstrate how molecular charge asymmetry can control the size of condensates! Work done in collaboration with @zwickergroup.bsky.social!!
Theory led by Chengjie Luo and simulations by @nathanieldhess.bsky.social!!
pubs.acs.org/doi/10.1021/...
Theory led by Chengjie Luo and simulations by @nathanieldhess.bsky.social!!
pubs.acs.org/doi/10.1021/...
Theory of Condensate Size Control by Molecular Charge Asymmetry
Biomolecular condensates are complex droplets comprising diverse molecules that interact by various mechanisms. Condensation is often driven by short-range attraction, but net charges can also mediate...
pubs.acs.org
September 30, 2025 at 5:06 AM
Our latest work from a stimulating collaboration with @jerelleaj.bsky.social and @nathanieldhess.bsky.social is out now!
A great example of a totally unplanned discovery in our group, spearheaded by a Bachelor and a PhD student! Curiosity wins 🥳
New preprint 🎉
What began as Frieder Johannsen’s bachelor thesis in the @zwickergroup.bsky.social (which I had the pleasure to supervise) evolved into our latest paper: “Chemically Active Liquid Bridges Generate Repulsive Forces” — unlike passive ones, which attract.
📄 arxiv.org/abs/2509.18777
What began as Frieder Johannsen’s bachelor thesis in the @zwickergroup.bsky.social (which I had the pleasure to supervise) evolved into our latest paper: “Chemically Active Liquid Bridges Generate Repulsive Forces” — unlike passive ones, which attract.
📄 arxiv.org/abs/2509.18777
September 29, 2025 at 5:31 PM
A great example of a totally unplanned discovery in our group, spearheaded by a Bachelor and a PhD student! Curiosity wins 🥳
Reposted by Zwicker Group
New preprint 🎉
What began as Frieder Johannsen’s bachelor thesis in the @zwickergroup.bsky.social (which I had the pleasure to supervise) evolved into our latest paper: “Chemically Active Liquid Bridges Generate Repulsive Forces” — unlike passive ones, which attract.
📄 arxiv.org/abs/2509.18777
What began as Frieder Johannsen’s bachelor thesis in the @zwickergroup.bsky.social (which I had the pleasure to supervise) evolved into our latest paper: “Chemically Active Liquid Bridges Generate Repulsive Forces” — unlike passive ones, which attract.
📄 arxiv.org/abs/2509.18777
September 29, 2025 at 5:17 PM
New preprint 🎉
What began as Frieder Johannsen’s bachelor thesis in the @zwickergroup.bsky.social (which I had the pleasure to supervise) evolved into our latest paper: “Chemically Active Liquid Bridges Generate Repulsive Forces” — unlike passive ones, which attract.
📄 arxiv.org/abs/2509.18777
What began as Frieder Johannsen’s bachelor thesis in the @zwickergroup.bsky.social (which I had the pleasure to supervise) evolved into our latest paper: “Chemically Active Liquid Bridges Generate Repulsive Forces” — unlike passive ones, which attract.
📄 arxiv.org/abs/2509.18777
It was fun to do a little interview and think about the relevance of our work for a more experimental and engineering inclined community.
David Zwicker, theoretical physicist and SynCellEU community member, explores how biological soft matter organises itself in space and time.
In our new article, we discuss his work, his contribution to #syncell research, and his advice to early-career researchers.
syntheticcell.eu/david-zwicke...
In our new article, we discuss his work, his contribution to #syncell research, and his advice to early-career researchers.
syntheticcell.eu/david-zwicke...
Meet the Community - David Zwicker
Theoretical physicist David Zwicker leads a research group that explores how biological soft matter organises itself in space and time
syntheticcell.eu
September 23, 2025 at 9:49 AM
It was fun to do a little interview and think about the relevance of our work for a more experimental and engineering inclined community.