Exponentially Large Probabilities in Quantum Gravity

TL;DR

This paper explores how topology change in quantum gravity leads to exponentially large wave functions, highlighting issues with wormhole effects and their implications for the universe's quantum state.

Contribution

It analyzes the impact of wormhole effects on the Wheeler-de Witt wave function, revealing exponential growth and associated conceptual challenges in quantum gravity.

Findings

Wave function is exponentially large with wormhole effects

Positive wormhole action allows redefinition of inner product

Negative wormhole action leads to more serious problems

Abstract

The problem of topology change transitions in quantum gravity is investigated from the Wheeler-de Witt wave function point of view. It is argued that for all theories allowing wormhole effects the wave function of the universe is exponentially large. If the wormhole action is positive, one can try to overcome this difficulty by redefinition of the inner product, while for the case of negative wormhole action the more serious problems arise.