Digest — 2026-10-01

Curated America/New_York (ET). Prefer arXiv / open sources. Verified via arXiv Atom API and cond-mat.soft / active-matter / colloidal keyword listings.
Focus: roughly since the 2026-09-30 digest (Wed→Thu). Prior items are not re-listed as “new today.”

At a glance

Diagram: original illustration of this digest’s key idea (not from the papers).

Highlights

1. Active spinners drive passive matter into chiral rotors

• Authors: Dennis Schorn, Anpuj Nair S, Stijn van der Ham, Benno Liebchen, Hanumantha Rao Vutukuri
• Submitted: 2026-09-30
• Link: https://arxiv.org/abs/2609.39439 
• Why newsworthy: Purely rotational magnetic spinners transfer chirality and edge currents to passive colloids; changing composition/attraction flips the organization inside-out so passive clusters rotate (with shared |Ω|∼R⁻² scaling) inside a chiral spinner fluid.
• Beginner hook: Spinning beads that never swim can still lend handedness and rim currents to quiet beads.
• Caveat: Magnetic-spinner / colloidal experiment + simulation.

2. Fully developed active turbulence defined through a nonequilibrium phase transition

• Authors: Lasse Bonn, Tianxiang Ma, Olga Bantysh, Wei Feng, Martin Cramer Pedersen, Guangyin Jing, Jordi Ignés-Mullol, Francesc Sagués, Nuno A. M. Araujo, Amin Doostmohammadi
• Submitted: 2026-09-30 (accepted Nature Physics)
• Link: https://arxiv.org/abs/2609.39348 
• Why newsworthy: Critical activity where vorticity nodal lines percolate (SLE₆ / critical percolation) and vortex centres form a rigid system-spanning cluster — an experimentally accessible definition of fully developed active turbulence (MT–kinesin + bacteria + simulations).
• Beginner hook: When opposite-spin regions knit into one system-spanning web, active turbulence has crossed a critical line.
• Caveat: Active-nematic / bacterial experiments + simulations.

3. A Reynolds-like criterion for the onset of universal active turbulence

• Authors: Kunal Kumar, Sandip Sahoo, Kirti Kashyap, Amal Manoharan, Siddhartha Mukherjee, Anupam Gupta, Samriddhi Sankar Ray
• Submitted: 2026-09-30
• Link: https://arxiv.org/abs/2609.39999 
• Why newsworthy: In TTSH dynamics, the universal spectrum E(k)∼k⁻³/² is reachable via multiple parameter routes that collapse onto a single Reynolds-like Re_act threshold.
• Beginner hook: One dial can mark membership in the universal active-turbulence club even when you turn different knobs.
• Caveat: Continuum theory / numerics.

4. Curvature-induced migration of small domains on lipid membranes

• Authors: Jaime Agudo-Canalejo
• Submitted: 2026-09-30
• Link: https://arxiv.org/abs/2609.39772 
• Why newsworthy: Small-domain energy on fixed curved membranes; size-dependent line-tension coupling can switch preferred seats (e.g. poles → equator on oblates) as domains grow and coalesce.
• Beginner hook: Shape alone seats membrane islands — and growing bigger can move your preferred seat.
• Caveat: Theory (Biophysical Journal Helfrich special-issue invite).

5. Training and memory in a randomly driven fractal gel

• Authors: Chloe W. Lindeman, Joshua D. Clugston, Justin C. Goodrich, Mark Sutton, James L. Harden, Robert L. Leheny
• Submitted: 2026-09-30
• Link: https://arxiv.org/abs/2609.40010 
• Why newsworthy: XPCS shows both cyclic and random shear train microstructural reversibility in a fractal nanoparticle gel; random-drive memory is readable with a standard amplitude protocol.
• Beginner hook: Messy random shaking can still teach a soft gel to remember how hard it was shoved.
• Caveat: Synchrotron XPCS / shear-cell experiment.

Stretch

• Ribbon gridshell metamaterials (2026-09-29): https://arxiv.org/abs/2609.38365 
• Cyclic active Brownian ratchet (2026-09-30): https://arxiv.org/abs/2609.39255 
• LC order + lipid membrane morphodynamics (2026-09-30): https://arxiv.org/abs/2609.40113 
• Density-aware MT active nematics (2026-09-29): https://arxiv.org/abs/2609.38520 
• Osmotically forced vesicle morphodynamics (2026-09-29): https://arxiv.org/abs/2609.38464 
• Packaged DNA sets virus electrostatic anisotropy (2026-09-29): https://arxiv.org/abs/2609.38429 

Safe classroom / discussion follow-ons

1. Inside-out spinner storyboard: Sketch CW spinners around a passive cluster, then flip to an active cluster in a passive matrix; annotate opposite rotation and a rim edge current (inspired by arXiv:2609.39439). Pencil/paper only — no magnets.
2. Ribbon gridshell angle sketch: On graph paper, draw two strip families crossing at fixed vs varying angles; discuss soft vs rigid sheets (inspired by arXiv:2609.38365). Paper/pencil only — no laser cutting.

Corpus mirror: /workspace/self-assembly-corpus/digests/2026-10-01.md.