Twist and Conic Mode Relaxation Times

For situations where an applied field is abruptly turned off, the relaxation constants depend on the kind of deformation involved. There are two distinct forms of deformation the pure twist one discussed previously and the so-called umbrella or conic mode. The first form of deformation involves fluid motion, whereas the latter does not. 

The dynamies of the field-induced twist deformation in cholesterics is described by an equation analogons to the equation for nematics  

The dynamieal equation for the conic distortion is much more complicated - and involves the other two elastic constants and.  

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