“It was pretty amazing how well the experimental data and numerical simulation matched,” Eckert mentioned. In truth, it matched so intently that Carenza’s first response was that it have to be improper. The crew jokingly fearful {that a} peer reviewer may suppose they’d cheated. “It really was that beautiful,” Carenza mentioned.
The observations reply a “long-standing question about the type of order present in tissues,” mentioned Joshua Shaevitz, a physicist at Princeton University who reviewed the paper (and didn’t suppose they’d cheated). Science typically “gets murky,” he mentioned, when knowledge factors to seemingly conflicting truths—in this case, the nested symmetries. “Then someone points out or shows that, well, those things aren’t so distinct. They’re both right.”
Form, Force, and Function
Accurately defining a liquid crystal’s symmetry isn’t only a mathematical train. Depending on its symmetry, a crystal’s stress tensor—a matrix that captures how a cloth deforms underneath stress—appears totally different. This tensor is the mathematical hyperlink to the fluid dynamics equations Giomi needed to make use of to attach bodily forces and organic capabilities.
Bringing the physics of liquid crystals to bear on tissues is a brand new option to perceive the messy, difficult world of biology, Hirst mentioned.
The exact implications of the handoff from hexatic to nematic order aren’t but clear, however the crew suspects that cells might exert a level of management over that transition. There’s even proof that the emergence of nematic order has one thing to do with cell adhesion, they mentioned. Figuring out how and why tissues manifest these two interlaced symmetries is a mission for the longer term—though Giomi is already engaged on utilizing the outcomes to grasp how most cancers cells circulate via the physique after they metastasize. And Shaevitz famous {that a} tissue’s multiscale liquid crystallinity may very well be associated to embryogenesis—the method by which embryos mildew themselves into organisms.
If there’s one central concept in tissue biophysics, Giomi mentioned, it’s that construction provides rise to forces, and forces give rise to capabilities. In different phrases, controlling multiscale symmetry may very well be a part of how tissues add as much as greater than the sum of their cells.
There’s “a triangle of form, force, and function,” Giomi mentioned. “Cells use their shape to regulate forces, and these in turn serve as the running engine of mechanical functionality.”
Original story reprinted with permission from Quanta Magazine, an editorially unbiased publication of the Simons Foundation whose mission is to reinforce public understanding of science by overlaying analysis developments and developments in arithmetic and the bodily and life sciences.