Most of my talk will be about anomalous thermal relaxations, such as the Mpemba effect. Towards the end of my talk, I will also highlight a few topics in population dynamics that I have been working on.
The Mpemba effect is a phenomenon when "hot can cool faster than cold" - a “shortcut” in relaxation to thermal equilibrium. It occurs when a physical system initially prepared at a hot temperature, cools down faster than an identical system prepared at a colder temperature. The effect was discovered as a peculiarity of water. Despite following observations in granular gasses, magnetic alloys, and spin glasses, the effect is still most often referred to as an “oddity” of water, although it is widespread and general. I will describe how to define a Mpemba effect for an arbitrary physical system, and show how to quantify and estimate the probability of the Mpemba effect on a few examples.
In the remaining time, I will briefly talk about the adaptation of bacterial populations and the immune system of bacteria with CRISPR. Besides being the biology's newest buzzword and favorite gene editing tool, CRISPR is also a mechanism that allows bacteria to defend adaptively against phages and other invading genomic material. From the standpoint of physics and biology, the coevolution of bacteria and phages yields fascinating open questions.