PHYS Seminar: “Evolutionary significance of non-Hermitian physics”, Aşkın Kocabaş, 3:30PM September 27 (EN)

Asst. Prof. Aşkın Kocabaş
Koç University, İstanbul

“Evolutionary significance of non-Hermitian physics”

Abstract
For those curious about nature, swarming animals, flocking birds, and schooling fish are among the most mesmerizing rituals easily observed in daily life. Even with our advanced technological and theoretical tools that decipher the dynamics of objects from the nano to the cosmological scale, our understanding of why animals perform these collective behaviors remains limited. Clearly, biological systems are controlled by intricately related genetic and physical factors. While it’s tempting to simply attribute this to the
complexity of biological systems, the question remains: Is there a more fundamental and convincing answer?

In this talk, I will review our recent experimental efforts to uncover simple physical and evolutionary principles behind these exotic phenomena. Recent advances in active matter physics offer new insights into the emerging behaviors of interacting entities. Similarly, biological systems consist of various interacting components, including both active and passive objects. We’ve discovered that the new concept
of nonreciprocity provides a remarkable bridge between Non-Hermitian physics and biology. Our experiments have highlighted critical nonreciprocal interactions spontaneously breaking chiral symmetry and leading to traveling waves, arrested phase separation, and edge states in active microbial populations. While these concepts are well-established in condensed matter physics, I will discuss their potential evolutionary implications promoting collective behaviors. Additionally, I will demonstrate how widespread these responses are across different microbial communities, ranging from bacterial biofilms to worms.

Finally, I will try to convince attendees that the interplay between the seemingly unrelated fields of non-Hermitian physics and biology offers valuable insights into the complexities of collective behaviors.

Date : September 27, 2023 Wednesday
Time : 15:30
Place : SA-240

All interested are cordially invited.