AI summary · arXiv: 2010.02845v5 · cond-mat.stat-mech

Topology protects chiral edge currents in stochastic systems

Evelyn Tang, Jaime Agudo-Canalejo, Ramin Golestanian
Original paper · DOI 10.1103/physrevx.11.031015 Submitted to arXiv on 06 Oct. 2020 Phys. Rev. X 11, 031015 (2021) 14 pages, with appendices and 3 supplementary videos License: NONEXCLUSIVE-DISTRIB 1.0

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The essentials

  • Construction of systems with time-scales significantly longer than individual components is a fundamental objective in synthetic biology and materials self-assembly.
  • Two-dimensional stochastic networks inspired by living systems exhibit chiral edge currents in configuration space due to topological phases.
  • Networks feature non-Hermitian properties such as exceptional points, vorticity, and localization of edge states.
  • Edge currents associated with macroscopic timescales can be manipulated by adjusting parameters to induce diverse dynamical behaviors.
  • Research provides a novel topological formalism for stochastic systems and insights into non-Hermitian physics, opening avenues for predicting resilient dynamical states.

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AI-generated keywords: Synthetic biology materials self-assembly stochastic networks topological phases emergent behaviors

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In the realm of synthetic biology and materials self-assembly, the construction of systems with time-scales significantly longer than those of their individual components is a fundamental objective. Drawing inspiration from living systems, where robust global behavior emerges despite the stochastic nature of underlying processes, researchers Evelyn Tang, Jaime Agudo-Canalejo, and Ramin Golestanian introduce two-dimensional stochastic networks comprising minimal motifs that represent out-of-equilibrium cycles at the molecular level. These networks exhibit chiral edge currents in configuration space, a phenomenon arising from topological phases due to bulk-boundary correspondence. The study delves into the unique properties of these networks, highlighting their non-Hermitian features such as exceptional points and vorticity while elucidating the localization of edge states. Notably, the emergent edge currents associated with macroscopic timescales and length scales can be manipulated by adjusting a small set of parameters to induce diverse dynamical behaviors including the establishment of a global clock, dynamic growth and shrinkage, and synchronization within the system. By providing a novel topological formalism for stochastic systems and offering fresh insights into non-Hermitian physics, this research opens avenues for predicting resilient dynamical states in both classical and quantum platforms. The findings presented by Tang et al., published in Phys. Rev. X 11 (2021), underscore the potential for harnessing topological protection to sustain chiral edge currents in stochastic systems, paving the way for advancements in understanding complex emergent behaviors in diverse scientific disciplines.

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