Toward fixing a framework for conformal cyclic cosmology

Understand

Conformal Cyclic Cosmology (CCC) is a cyclic model of the universe put forward by Sir Roger Penrose.

• A conformal invariance assumption in the neighbourhood of the crossover region between cycles (which Penrose calls aeons) allows successive space-times to be related by a conformal rescaling.
• A major open problem is how to choose the conformal factor in a unique way, and is a fundamental hurdle to further study.
• Proposals have been put forward by Newman, Tod and Nurowski, but they disagree in one way or another with Penrose's original assumptions as well as each other.