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Are there geometric objects underlying the cosmological observables of Tr $\phi^3$ theory, just as associahedra underlie scattering amplitudes? In this talk, I will describe a new class of polytopes that answer this question. I will start by reviewing the perturbative computation of the wavefunction, and its organization in terms of collections of non-overlapping subpolygons living inside the momentum polygon. This combinatorial information is much richer than that of Tr $\phi^3$ amplitudes, where the diagrams correspond to triangulations of the same polygon. Nonetheless, as I will show the geometric descriptions are closely related: the polytopes for the wavefunction — “cosmohedra” — are obtained by "blowing up" the faces of the associahedron in a natural way. Finally I will explain how the combinatorics behind correlation functions — which are given by blend of those of scattering amplitudes and wavefunctions — are also captured by the "correlatron", which is a one-higher dimensional polytope, sandwiched between associahedra and cosmohedra as the "top" and "bottom" facets in the extra dimension. I will give a concrete definition of these new polytopes, show how they work in some simple examples, and describe a number of open questions about the physics and mathematics associated with them.