Beyond Boundary Conditions: General Cosmological Theories

TL;DR

This paper explores a broader class of quantum cosmological theories by conditioning on fixed sequences of events, extending beyond traditional boundary condition approaches to better assess initial condition hypotheses.

Contribution

It introduces a new framework for quantum cosmology that conditions on fixed event sequences, expanding the scope of possible theories beyond time-symmetric boundary conditions.

Findings

Proposes a general class of cosmological theories conditioned on fixed events.

Suggests these theories can help evaluate the sufficiency of initial conditions.

Highlights potential for more flexible modeling of cosmological phenomena.

Abstract

Time-symmetric cosmological theories, in which the initial and final states are arranged to have similar features or are independently fixed, have been quite extensively discussed in the literature. However, a more general and perhaps more useful possibility seems, surprisingly, never to have been considered. Quantum cosmology, like any inherently probabilistic dynamical theory, can be modified by conditioning on the occurrence of a sequence of cosmological events fixed a priori and independently of the hamiltonian and initial state. These more general theories provide a natural class of alternatives which should eventually be useful in quantifying how well the hypothesis that initial conditions suffice is supported by the data.