I discuss various features of scalar theories with higher-derivative terms in the action. These include: a) classical scattering at length scales much larger than the fundamental scale (classicalization), b) classical solutions that can be interpreted as branes connected with throats or as shock waves, c) the renormalization of a subclass of such theories, d) the connection with the Galileon theory and the scenario of asymptotic safety of gravity.

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Note unusual day !!!