Embedding Non-Linear Structures in f(R) Cosmologies
  When using Einstein's equations, there exist a number of techniques for
embedding non-linear structures in cosmological backgrounds. These include
Swiss cheese models, in which spherically symmetric vacua are patched onto
Friedmann solutions, and lattice models, in which weak-field regions are joined
together directly. In this talk we will consider how these methods work in f(R)
theories of gravity. We will show that their existence places constraints on
the large-scale expansion of the universe, and that it may not always be
possible to consider the Friedmann solutions and weak-field solutions of a
theory independently from each other.
