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In this paper we analyze local structure of several chaotic attractorsrecently suggested in literature as pseudohyperbolic. The absence of tangenciesand thus the presence of the pseudohyperbolicity is verified using the methodof angles that includes computation of distributions of the angles between thecorresponding tangent subspaces. Also we analyze how volume expansion in thefirst subspace and the contraction in the second one occurs locally. For thispurpose we introduce a family of instant Lyapunov exponents. Unlike the wellknown finite time ones, the instant Lyapunov exponents show expansion orcontraction on infinitesimal time intervals. Two types of instant Lyapunovexponents are defined. One is related to ordinary finite time Lyapunovexponents computed in the course of standard algorithm for Lyapunov exponents.Their sums reveal instant volume expanding properties. The second type ofinstant Lyapunov exponents shows how covariant Lyapunov vectors grow or decayon infinitesimal time. Using both instant and finite time Lyapunov exponents wedemonstrate that specific to the pseudohyperbolicity average expanding andcontracting properties are typically violated on infinitesimal time. Instantlyvolumes from the first subspace can sometimes be contacted, directions in thesecond subspace can sometimes be expanded, and the instant contraction in thefirst subspace can sometimes be stronger than the contraction in the secondsubspace.

Lyapunov analysis of strange pseudohyperbolic attractors: angles between tangent subspaces, local volume expansion and contraction