Disentangling the cosmic web. I. Morphology of isodensity contours

We apply Minkowski functionals and various derived measures to decipher the morphological properties of large-scale structure seen in simulations of g ravitational evolution. Minkowski functionals of isodensity contours serve as tools to test global properties of the density field. Furthermore, we id entify coherent objects at various threshold levels and calculate their par tial Minkowski functionals. We propose a set of two derived dimensionless q uantities, planarity and filamentarity, which reduce the morphological info rmation in a simple and intuitive way. Several simulations of the gravitati onal evolution of initial power-law spectra provide a framework for systema tic tests of our method.