# Resources

## Publications

• ### Hyperuniform Active Chiral Fluids with Tunable Internal Structure

Author(s): Bo Zhang and Alexey Snezhko Large density fluctuations observed in active systems and hyperuniformity are two seemingly incompatible phenomena. However, the formation of hyperuniform states has been recently predicted in nonequilibrium fluids formed by chiral particles performing circular motion with the same handedness. Here … [Phys. Rev. Lett. 128, 218002] Published Fri May 27, 2022
• ### Extending the Lifespan of Multicellular Organisms via Periodic and Stochastic Intercellular Competition

Author(s): Tao Wen, Kang Hao Cheong, Joel Weijia Lai, Jin Ming Koh, and Eugene V. Koonin Resolution of the intrinsic conflict between the reproduction of single cells and the homeostasis of a multicellular organism is central to animal biology and has direct impact on aging and cancer. Intercellular competition is indispensable in multicellular organisms because it weeds out senescent c… [Phys. Rev. Lett. 128, 218101] Published Fri May 27,...
• ### Asymptotic Absorption-Time Distributions in Extinction-Prone Markov Processes

Author(s): David Hathcock and Steven H. Strogatz We characterize absorption-time distributions for birth-death Markov chains with an absorbing boundary. For “extinction-prone” chains (which drift on average toward the absorbing state) the asymptotic distribution is Gaussian, Gumbel, or belongs to a family of skewed distributions. The latter two ca… [Phys. Rev. Lett. 128, 218301] Published Tue May 24, 2022
• ### Small Obstacle in a Large Polar Flock

Author(s): Joan Codina, Benoît Mahault, Hugues Chaté, Jure Dobnikar, Ignacio Pagonabarraga, and Xia-qing Shi We show that arbitrarily large polar flocks are susceptible to the presence of a single small obstacle. In a wide region of parameter space, the obstacle triggers counterpropagating dense bands leading to reversals of the flow. In very large systems, these bands interact, yielding a never-ending cha… [Phys. Rev. Lett. 128, 218001] Published...
• ### Continuum Field Theory for the Deformations of Planar Kirigami

Author(s): Yue Zheng, Imtiar Niloy, Paolo Celli, Ian Tobasco, and Paul Plucinsky Mechanical metamaterials exhibit exotic properties that emerge from the interactions of many nearly rigid building blocks. Determining these properties theoretically has remained an open challenge outside a few select examples. Here, for a large class of periodic and planar kirigami, we provide a co… [Phys. Rev. Lett. 128, 208003] Published Fri May 20, 2022
• ### Susceptibility of Polar Flocks to Spatial Anisotropy

Author(s): Alexandre Solon, Hugues Chaté, John Toner, and Julien Tailleur We study the effect of spatial anisotropy on polar flocks by investigating active $q$-state clock models in two dimensions. In contrast to the equilibrium case, we find that any amount of anisotropy is asymptotically relevant, drastically altering the phenomenology from that of the rotationally inva… [Phys. Rev. Lett. 128, 208004] Published Fri May 20, 2022
• ### Thermal Fluctuations of Singular Bar-Joint Mechanisms

Author(s): Manu Mannattil, J. M. Schwarz, and Christian D. Santangelo A bar-joint mechanism is a deformable assembly of freely rotating joints connected by stiff bars. Here we develop a formalism to study the equilibration of common bar-joint mechanisms with a thermal bath. When the constraints in a mechanism cease to be linearly independent, singularities can appear … [Phys. Rev. Lett. 128, 208005] Published Fri May 20, 2022