GAUSSIAN RANDOM-FIELD DESCRIPTION OF FLUCTUATING FLUID VESICLES

Gaussian random processes on spheres are studied as models of fluctuat ing fluid vesicles. We derive expressions for the mean volume, surface area, curvature, and square curvature of vesicles with arbitrarily st rong Gaussian fluctuations. A Feynman-Hellman approximation allows, by variational minimization, a consistent derivation of structure factor and free energy of vesicles. As an example, we investigate a fluctuat ing vesicle with fixed mean surface area and volume for a wide range o f values of the bending modulus.