Noah Ziethen
@nziethen.bsky.social
Postdoctoral researcher in theoretical physics, curious about living and active matter.
By combining the fixed bridge radius with a thin-interface approximation, we derived an analytic force expression for a cylindrical active bridge.
✅ It matches the scaling found in simulations—showing that size control is the main driver of the observed effects.
✅ It matches the scaling found in simulations—showing that size control is the main driver of the observed effects.
September 29, 2025 at 5:18 PM
By combining the fixed bridge radius with a thin-interface approximation, we derived an analytic force expression for a cylindrical active bridge.
✅ It matches the scaling found in simulations—showing that size control is the main driver of the observed effects.
✅ It matches the scaling found in simulations—showing that size control is the main driver of the observed effects.
Why?
Passive: Stretching increases surface energy, pulling walls together
Active: Chemical reactions maintain fixed bridge radius regardless of wall separation
👉 The bridge doesn't thin but can grow in volume → it is energetically favorable for the walls to move apart, generating repulsion.
Passive: Stretching increases surface energy, pulling walls together
Active: Chemical reactions maintain fixed bridge radius regardless of wall separation
👉 The bridge doesn't thin but can grow in volume → it is energetically favorable for the walls to move apart, generating repulsion.
September 29, 2025 at 5:17 PM
Why?
Passive: Stretching increases surface energy, pulling walls together
Active: Chemical reactions maintain fixed bridge radius regardless of wall separation
👉 The bridge doesn't thin but can grow in volume → it is energetically favorable for the walls to move apart, generating repulsion.
Passive: Stretching increases surface energy, pulling walls together
Active: Chemical reactions maintain fixed bridge radius regardless of wall separation
👉 The bridge doesn't thin but can grow in volume → it is energetically favorable for the walls to move apart, generating repulsion.
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