Thomson versus Hubble: Clock synchronization in a concordant Universe

Persistent discrepancies between different cosmological measurements continue to challenge our theoretical understanding of cosmic evolution and of the energy content driving it. I will argue that a concordant model of the Universe must maintain the synchronization between the different clocks governing its dynamics as its physics deviates from LCDM. This presents a serious challenge to our contemporary understanding of fundamental physics. I will present potential ways to maintain the synchronization between the different clocks of the Universe, highlighting in each case the high theoretical price that one must be willing to pay to go down this route.