“It was fairly superb how properly the experimental knowledge and numerical simulation matched,” Eckert mentioned. In truth, it matched so intently that Carenza’s first response was that it should be fallacious. The staff jokingly fearful {that a} peer reviewer would possibly assume they’d cheated. “It actually was that lovely,” Carenza mentioned.
The observations reply a “long-standing query about the kind of order current in tissues,” mentioned Joshua Shaevitz, a physicist at Princeton College who reviewed the paper (and didn’t assume they’d cheated). Science usually “will get murky,” he mentioned, when knowledge factors to seemingly conflicting truths—on this case, the nested symmetries. “Then somebody factors out or exhibits that, properly, these issues aren’t so distinct. They’re each proper.”
Kind, Power, and Perform
Precisely defining a liquid crystal’s symmetry isn’t only a mathematical train. Relying on its symmetry, a crystal’s stress tensor—a matrix that captures how a fabric deforms below stress—seems completely 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 technique to perceive the messy, sophisticated world of biology, Hirst mentioned.
The exact implications of the handoff from hexatic to nematic order aren’t but clear, however the staff suspects that cells might exert a level of management over that transition. There’s even evidence that the emergence of nematic order has one thing to do with cell adhesion, they mentioned. Determining how and why tissues manifest these two interlaced symmetries is a challenge for the longer term—though Giomi is already engaged on utilizing the outcomes to know how most cancers cells move by way of 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 offers 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 kind, drive, and performance,” Giomi mentioned. “Cells use their form to control forces, and these in flip function the operating engine of mechanical performance.”
Original story reprinted with permission from Quanta Magazine, an editorially impartial publication of the Simons Foundation whose mission is to boost public understanding of science by masking analysis developments and tendencies in arithmetic and the bodily and life sciences.