Extended Data Fig. 4: Pair-creation events occur where viscometric surfaces converge on bend walls.
A long bend wall drives viscometric flow along much of its backbone. A pair creation event occurs where the bend wall and the two viscometric surfaces converge to meet at a point. Black arrow indicates the arrow of time. Colourmap identifies line-like bend walls through the strongly-negative SSB (same as Fig. 3a). Zero-isolines of the \({\mathcal{Q}}\)-criterion are shown as solid lines, coloured in red for clockwise and blue for anti-clockwise. Nematic +1/2 defects marked by green comet-shaped symbols and minus-half defects by dark blue-trefoil shaped symbols (section ‘Defect analysis’).
