AUTHOR=Cohen-Cobos Daniel , Sanders Kiyomi , DeGroot Laura , Guarnera Heather , Leary Cody , Lindner John F. , Manz Niklas 

TITLE=Chemistry does general relativity: reaction-diffusion waves can model gravitational lensing

JOURNAL=Frontiers in Physics

VOLUME=11

YEAR=2024

URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2023.1315966

DOI=10.3389/fphy.2023.1315966

ISSN=2296-424X

ABSTRACT=<p>Gravitational lensing is a general relativistic (GR) phenomenon where a massive object redirects light, deflecting, magnifying, and sometimes multiplying its source. We use reaction-diffusion (RD) Belousov-Zhabotinsky (BZ) chemistry to study this astronomical effect in a table-top experiment. We experimentally observe BZ waves passing through non-planar, quasi-two-dimensional molds and reproduce the waveforms in computer simulations using planar RD waves propagating with variable diffusion. We tune the variable diffusion to match the Schwarzschild-coordinate light speed near a spherical mass so the RD propagation approximates Einstein’s famous light deflection relation. We discuss varying the diffusion or reaction rates with a gel matrix or with illumination, electric field, or temperature gradients.</p>